The number of apps one installs has to do with what the iPad is to you.
For example, someone who likes to play games will get huge collections.
Someone who likes to tinker with the iPad will get it JB and get the related apps and that's fine. I think that JBreaking the iPad is in the same vein as hot rodding a car. There are loads of things that need to be fixed with the iPad since it's been castrated.
(Btw, that's my first and only comment on JBing the iPad. I drive at low speeds so a car is a point AB thing to me, I have no interest in changing what Apple created)
I use the iPad solely for displaying content, books, magazines, photos, movies, occasionally for music since it has a built-in speaker that my iPod doesn't have, for file management, drawing and other cool uses like the GPS. Oh, I forgot news.
So, in total I have 37 apps on the iPad and about ten more in iTunes that I did not like for some reasons.