They do, but only because almost everyone I know uses GMail. I migrated away several years ago.
But seriously, Google's computers do, but humans at Google almost never do (occasional rogue employees being the exception). They do a few things when they scan it:
- Spam filtering (most e-mail providers do this; some give the option to disable it)
- Matching e-mails to keywords for ad placement (almost all free e-mail providers do this)
- Classification by category (newsletter, main inbox, etc.)
- Apparently some new stuff like "you should follow up on this since it's been 3 days"
I do agree that the algorithmic help can get a bit creepy at times. That in part, but moreso concerns - ethical, rather than practical - over surveillance (the NSA's PRISM program, which Google participates in), and finding an option with a better user interface, are what led to me switching away from GMail.
From a security standpoint, unless you're potentially a target of the U.S. government, GMail is one of the top tier options (though there are other equally secure options as well), and they are notable in particular for their protections for Tibetans in China. But they may not be the best option if you aren't a fan of targeted advertisements based on your private e-mail messages, or other helpful-but-somewhat-creepy ways it can make your life easier.
