Pros
Lots of really smart engineers Lots of really huge scale systems Plenty of opportunities Casual culture The usual free food, free snacks, onsite gym kind of Silicon Valley perks
Cons
Quarterly Performance Reviews (QPRs): They are as awful as you've heard. Every quarter you go through a full-on review cycle. That means having to spend a lot of time justifying the work you've done, a lot of time filling out peer reviews for your coworkers, and a lot of time generally worrying about your status there. Yahoo! uses a stack-ranking system where everyone is ranked from first to worst. Everyone is put into a bell curve and all slots in that curve must be filled. That means that if you're on a high performing team you may wind up in the lower quartiles even if you do good work. When I worked there if you wound up one standard deviation to the right for two consecutive quarters you were put on a PIP. I've heard from friends who still work there that now if you wind up in a lower quartile on *one* QPR you're not put on a PIP, you're simply fired. That's right folks, one bad quarter and you're out. They pretend that the reviews are objective, but they're not. How can they be? It's a nasty political system. If you're not into that, stay away. The company has been sputtering along for 8 years now. Despite many many changes in top leadership and lots of big talk, nothing has really changed. Yahoo! is always a takeover target. There is always a threat of layoffs, although now with the harsh QPR system there's a constant stealth layoff going on. Also as I was leaving I noticed that a new harsher, nastier engineering culture was taking hold there. Engineers talked gleefully of "getting rid of the dead weight" (translation: mass firings). If you weren't absolutely stellar you were crap. If you're anything less than a top-tier engineer, stay away. Your life there won't be pleasant. If you are a top-tier engineer, stay away, there are *much* better companies in the valley where you can really shine. If you need a job out of college, it's probably a fine place to go. Yahoo! still looks good on the resume. Just don't plan to stay there too long.