I gave the pathfinder rules a skim, and I think that, while I like the extra ability/feat options as well as (for it's my impression) the flexibility of classes being greater, the rules aren't an improvement over 4e's. Though, I read that the pathfinder campaigns are better than 4e's.

Considering that, I think the most logical option is to run vanilla 4e for the people who need to get play experience (myself included) and then adapt the extra features of pathfinder into the 4e rules.