I've worked at a couple very high-profile companies in the Valley and have never felt this prestige primarily because I don't hang out with complete douchebags.
If people get all starry-eyed when you announce the company you work for; run in the opposite direction. Also, don't kidd yourself, you and I know both know you're not working on anything that cool. Especially because almost everyone works on a team so responsibility is pretty spread out.
And even if you are working on the very algorithm that determines which ads are shown when, you're still buried in seventeen layers of process and bureaucracy for a change or product that will probably never ship or will take years to market.
The day-to-day is about unglamorous as it gets. People need to realize the big "names" in the Valley are simply large corporations.