The good health insurance can be nice and that 401k matching is powerful. Compound interest is pretty awesome too. It can be nice to work with others and have proper design and product management support and if you can seek out the best managers you can learn a lot from them but all of these things are hit or miss. I sure liked it better than my stint as an IT consultant and Network Engineer years ago but I don't think I'll ever be able to convince myself go back after start my own thing. That said, change can be good for you.
you'll have a lot more time to browse the web and get paid for it.
Depends on the company. At some of the better ones, don't underestimate the opportunity to work with really smart peers. Even some of the not-so-hot ones like IBM or Yahoo have really smart engineers locked up inside them.