Their interview process will directly give you the feel of how it could be to work with them. In one day, they will finish off all the rounds of interview, in all 4-5 rounds! Their interviewing approach can be summed up in these words.. "ok lets talk business" .. so they wud want u to actually show how well u can code on the spot, how quick ur logical and analytical thinking is, your knowledge span in the area and how well you can handle working under some level of stress.
That's not all. Having all of the above talent doesn't ensure you will be hired. They say, you can be a genius but bad at adopting to team environment or resistant to learning new stuff and stuff like that. So you gotta have some people skills too. These guys are very humble and flexible. Great to talk to.
It's easy to get offended by them sometimes or maybe you would just feel low if you're not selected at such a company. But never mind. For a company of this level, you should forgive yourself for not getting selected as long as you made it at least half way through or more.
If you get selected, you can assume, tomorrow Google, Facebook and the likes can hire you too.