Well, that's true, but the iPad 3 is more significant than most technological announcements, because it sets the bar for other technologies to follow. The iPad is the first product in Apple's product line that makes use of its new chips. It's generally the most technologically advanced piece of hardware in the mobile world - the first device to use "next generation" chips. Most devices that come shortly before the new iPad are only marginal improvements (i.e. comparable generation, same sort of league, but a little faster overall than the current iPad) -- the new iPad tends to blow these devices away (the same is true of the iPhone). And the devices that come out shortly after the iPad are usually still in the old generation. By the time other manufacturers make next gen devices, the iPad is already 6 months old.
Well firstly there are x86 slates that are way ahead, though admittedly for Android devices (and until Windows 8 comes out), the OP probably isn't interested in those. But nonetheless, if you're talking about processor speed as the only thing that matters, this isn't true.
Do you have a reference for processor comparisons, out of interest? It's hard to compare because of Apple often using slightly different CPUs. Do you also have a reference for IPad 3 specifications?
As for the IPhone, many manufacturers put out high end phones that push the spec when they are first released. Plus, not everying cares about raw processor speed - there are many other issues. Saying Apple is way ahead is just showing your personal opinion. But even if the OP does only care about Apple, it will still always be true that waiting for the next IPad/IPhone will get him something better. Let's look at some specs:
IPhone (June 2007): 412MHz ARM, 128MB RAM, 480x320 display, couldn't do apps, no 3G.
Nokia 5800 (April 2008): 434MHz ARM11, 128MB RAM, 640x360 display, could do apps, 3G.
IPhone 3G (July 2008): 412MHz ARM, 128MB RAM, 480x320 display, could do apps, 3G.
IPhone 3GS (June 2009): ARM Cortex A8, 256MB RAM, 480x320 display.
HTC Desire (February 2010): 1GHz Snapdragon, 576MB RAM, 800x480 display.
Samsung Galaxy S (June 2010): ARM Corext A8, 512MB RAM, 800x480 display.
IPhone 4 (June 2010): ARM Cortex A8, 512MB RAM, 960x640 display.
HTC Desire S (February 2010): 1GHz Snapdragon, 768MB RAM, 800x480 display.
So it's not really true that IPhone is the one the sets the next hardware generation, either compared to other phones, or even when just looking at IPhones. And no, don't back pedal and come up with ways on how you like the IPhone to other phones. I'm not interesting in a phone-debate which is just opinions - I'm pointing out that there isn't any kind of industry trend setting generational leap with every Apple release, when viewed objectively. Many manufacturers have their own pluses and minuses, and move the boundaries forward in various areas. If you think that each new IPhone released blowed everything away, and only Apple do that, then that's your opinion. Many people like (and buy) other phones too.
Plus your argument doesn't change my point in any sense - it's always true if you wait, there'll be something better soon. Sure, maybe it's a point if the next device is right round the corner, but we have no idea here. When IPad 3 is out, people will go "And after IPad 3, there'll be an IPad 4!"
ETA: Also go to
http://en.wikipedia.org/wiki/Comparison_of_tablet_computers , look at 8" and larger, and view by Release Date. Sorry, I don't see any evidence of what you claim. IPad 2 got us 2 CPU cores, but it wasn't the first (plus you think that cores don't matter anyway). A mere month later, the ASUS Transformer and Samsung Galaxy Tab 10.1 upped the resolution to 1280x800, which Apple have yet to beat. Of course, I realise these charts don't show exact CPU and GPU performance comparisons, but sorry, I don't see where some new generation was ushered in with IPad 2; and I see gradual increases coming with releases from many manufacturers.
So yeah, it's not really a smooth continuum of technological advancement; the iPad usually marks a step-change in technology. It puts itself in a different league to existing devices, and other manufacturers spend the next 6 months playing catch-up. The new iPad is usually the start of the next cycle, so buying just before its release pretty much guarantees you'll be paying over the odds for old hardware.
This reads like an Apple press release :/
I never said it was a smooth continuum. But equally, it's still true that if you wait, you get something better. Even if you are obsessed by Apple, that's still true. But for the rest of us - Apple were playing catchup too (e.g., copy/paste, video calling, voice recognition, 3G, apps). There are lots of phones out there, all pushing the boundaries in different areas (e.g., Nokia's recent 808 announcement, for camera phones) - and as I show above, I see no evidence of quantum leaps in hardware that start with each IPhone release.
And yes, I agree that you don't want to buy "just before" - but then again, that still applies to just before the new version of any hardware that you might be getting. E.g., buying a Samsung Galaxy S just before the S2 came out.
But do we actually have a release date? Or is the "very soon" still the "very soon honest" that we've heard rumours for about a year now?
A comparison to the Vita is useless even if they could perform the same tasks. The Vita's screen is 5" and has a resolution of 960x540. The iPad 2 is 10", and assuming the iPad 3 uses a 'retina' display, will have a resolution of something like 2000x1500.
Assume, assume, assume. Did the OP say he must have 10"? And you're saying that an unreleased future device will be better than an existing device? That's hardly unsurprising - and that's exactly the point I'm making. Of course waiting for future devices will get you something better. If we're discussing vaporware, I'm going to tell the OP to wait for Vita 2.
If you narrow down the category of interest to be something "just like the IPad", so any competition can be dismissed as being too different, of course the IPad will come out with no competition. But I could equally do that with the Vita - or any other tablet, or any smartphone.
So in summary, (a) I disagree that Apple are always streets ahead in hardware with every release, (b) this is much to do with personal opinion on what things you consider important (why is it with Apple, people always have to present opinion as fact?), (c) even if the OP only cares about Apple, it's still always true that "waiting for the next release will get something better". There will always be media hype and rumour vaporware about "IPhone/IPad x+1 rumoured to follow IPhone/IPad x!"
Secondly, the Vita's SoC is the same as the iPad 2, just with 4 cores instead of 2. That's not a generational leap in processing ability - it's just throwing an extra core in there that developers may not even know how to use.
The free lunch is over. Processor improvements are now coming primarily in extra cores rather than making single cores go faster.
You claim that Apple devices alone set the new standard in chip hardware, but then a counter argument is dismissed, because twice as many cores apparently isn't an improvement? By that logic, I could come up with a reason to dismiss whatever improvements the IPad 3 brings (like 2000x1500 offering no real advantages once you've already got 1200x800, on that sized device). You can't have your cake and eat it - which is it? Is it that it's the processor that's important? Or is it not so important?
(I'm also confused that you underline and bold "2" in IPad, as if beating the latest top-of-the-line from Apple's product line is somehow not saying anything, and instead their released product is supposed to compete with unreleased vaporware from Apple. If that's the case, let's start assuming what Vita 2 will have, and compare that.)