Yes, I much prefer working in a small company for all these glorified (and popular here) reasons but it doesn't mean startups are good for everybody. In fact I believe startups do not appeal to real hackers, guys who we quote and admire. My limited personal experience confirms this too: smart people I know work at IBM, Motorola, Google and Microsoft and they're HAPPY.
And this is why:
Let's face it: in a startup, most often than not you're working on something trivial, technically simple, something that can be "released often, released early". Some minor "incremental improvement", and you've got PG books saying "it's OK". At a startup you (most probably) will be working on something that most of your friends will call "stupid shit" behind your back. Let's not pretend this elephant isn't there. There are exceptions to every rule, but it's a rule nevertheless.
And this is something I miss the most: an opportunity to work on hard problems, not necessarily even succeeding: this is why startups almost never try. And this is why my ideal "exit strategy" is to cash out (some day) and spend my days in academia.
Wow... This was very sudden (even for me) and perhaps misplaced rant.