4e psionics is going to be...tricky. The vast majority of people who like psionics, loved 3.5's rendition of them, and very, very strongly want a mechanical difference between them and other types of casters - which simply won't happen in 4e. Most of the people that dislike psionics, well, dislike them. I think 4e is going to be in a really rough spot as far as psionics goes, simply because they're 1) coming out of a psionics system that was, in my opinion, the very avatar of elegence and simplicity, and 2) the vast, vast majority of people who like psionics don't want them to be just a reskinned wizard, and want different game mechanics from how wizards do things to fit the idea of them gaining their power in a radically different way.