In Silicon Valley, a Flight to Safety
online.wsj.com
online.wsj.com
Personally, I think that if fears like this are enough to send you packing to a bigcorp, then you should probably be working for a bigcorp. This doesn't mean you're uncreative or overly fearful, bu the way. I've worked for bigcorps, and they actually aren't terrible (though I did work for Sun Micro, which is (or at least was) very laid back for a bigcorp). But I have so much more impact on the small startup-ish company I work for now.
If you want to live in the edgier world of startups and small companies, well then you're going to have to stare down some fears. These fears aren't meaningless.