I agree with the limits. It does seem to encourage the same people year after year, although I've seen some people dropped and new ones come on. It might encourage less competition, however, since people that were doing to be dropped might stop and new MVPs would get accepted with less effort.

There's definitely some prestige for those people that are MVPs for 6 years (or some other number). Quite a few of these people are very active in the community constantly.

Not sure I want to see more guidelines, but perhaps some comment on what things MSFT saw as most valuable over the last year.