Pros
Great learning experience; fast-paced atmosphere; global outlook. It offered me many opportunities for travel and learning about other cultures when working on various projects, which I would not have gotten in other companies. My team members in countries all around the globe were mostly fantastic, motivated, intelligent people who really care about their jobs. Dell also does pay more than most companies; however, you'll spend so much time working, you won't have much time to spend the money! The benefits package is also excellent, with (I think) 4% 401K matching, and good health / vision / dental benefits as well.
Cons
Very long work days--7AM to 10PM is very common (although not all in the office--they do let you take calls at home). Very little chance for advancement if you don't fit into their "mold" and aren't comfortable constantly promoting yourself to execs. Excelling at your job isn't enough to get ahead; you need to be extremely competitive (one might say "cut-throat") and be willing to advance on the backs of others. They had made some efforts at work-life balance a few years ago, but now with many of the formerly US-based jobs going overseas, you'll spend a majority of your time on conference calls, early morning and late night.