Pros
Centaur is the most amazing place I have ever worked. The company is led by IBM Fellow Glenn Henry, and its guiding philosophy is that if you take really smart, driven people, treat them well, point them towards a problem (in this case, x86 CPU design), and get out of their way as much as possible, they will out-produce any other set of engineers on the planet. There are around 100 people in the entire company, and that includes architecture, logic design, DV, circuit design, physical design and layout. There are no managers -- the closest Centaur has is "technical lead", which is 90% technical, 10% lead. It's important here to distinguish: as others said, there is not a lot of direction. There is a lot of help, though. Everyone I worked with over the past ten years has been amazing, and they're always willing to lend a hand. So, if you aspire to management, or aren't remarkably self-directed, Centaur might not be for you. On the other hand, I spent 11 years there, and I learned more by working with the people there than I thought was possible. If you really want to grow as an engineer and learn from truly experienced designers, this is the place to be. You are given as much responsibility as you can take on, and people take a lot of pride in the work they do.
One of the more interesting manifestations of this is the terminology -- often, design blocks are referred to by their owners, not their design names. So, in conversations, you hear "and we send this to Doug", or "...and there's a bug in John." People take a lot of ownership at Centaur, and they work hard and are proud of what they've accomplished.
Also, they are realistic about pay -- they know this plan only works if they hire amazing people, and their compensation reflects that. Benefits are great, everyone has an office, lunch is provided; again, they believe that happy employees will give their best, and history seems to have proven them right.
Cons
If you want to be a manager, look elsewhere. I generally lean heavier to the "work" side of work/life balance, but you don't have a manager to assign priorities. Workloads can mount up quickly.
Lunch is free, and while there are lots of healthy options, there are also lots of unhealthy options, and snacks are also provided. You will gain weight. Plan for it.