I don't understand how anyone could feel 'ripped off' by PTW. Are you upset that Conquests included PTW? Or that PTW wasn't as good as Conquests? My answer to the first problem is simple: If you bought PTW when it first came out (like I did), then you had a year's worth of gaming experiences that you wouldn't have had simply waiting for Conquests. And my answer to the second problem is simpler still: Conquests was better because it came later and built on PTW, just as PTW was better than the initial Civ III release because it came later and built on Civ III.
If you felt ripped off because they keep releasing new expansion packs that you have to spend money on, well, welcome to the world of PC gaming. If you want to avoid expansion packs, stick to the consoles. If you want to have all the Civ you can have for as little money as possible, then you'd better not buy Civ IV when it comes out. Because there will be expansion packs for that, as well. But I'm sure they'll follow tradition and release a complete all-packs-included version of Civ IV once Civ V is near completion, and you can go buy Civ IV then. Meanwhile, the rest of us will buy the stuff when it comes out, and we'll have lots of fun playing the game and discussing its merits and flaws here for at least three or four years, which means it will be money well-spent for us.