Pros
If you are an analyst at Gartner, you can have unmatched visibility within the technology space. You have no lack of companies and people who would like to talk with you, and you have a real opportunity to affect the business strategies of the largest and most important technology companies. Gartner is also an incredibly flexible and virtual company - with the vast majority of the analyst population working from home and in remote locations, as opposed to central offices.
Cons
Since everyone is working alone - there are a lot of loner type personalities. Thinking can be very "ivory tower" sometimes. Compensation is all over the board, and lots of bureaucracy. Performance targets for analysts change every year, or even mid-year, and there are too many different things that analysts have to focus on.