"Unlimited vacation" is also grossly misleading in SV though. I have seen very, very few companies that actually live up to their own hype about encouraging employees to take off as much time as they need.
More often than not, in SV at least, "unlimited vacation" policies is really just code for "don't take any". The small print is also "if you really do take a lot of time off, even if you're great, you don't belong in our Red-Bull-shotgunning startupy experience".
There's a war on for talent now. Be careful what you wish for.