When and if Paizo decides to do something with psionics, we'll be handling it pretty much entirely in-house, using some freelancers to create some of the support material (said freelancers being chosen by us from those we've worked with before and whom we trust to do the job right).
Regarding what needs adjustment from the 3.5 incarnation of psionics, I'd say pretty much all of it. It'd be a complete revision and overhaul, from the classes on down to the powers themselves.
As for how to get involved in the project... you basically need to be an established Pathfinder freelancer when we decide to start working on it, which means you should start now by taking part in RPG superstar, start pitching scenario ideas for the Pathfinder Society to Mark Moreland, and start submitting ideas to other publishers like Open Design and the like. Start building up your experience and portfolio, and if we like what we see, we might just start asking you to work on bigger projects. There's a LOT of competition in that area, though.
Time is still on your side though. We're probably still a year or two from seriously...
Thanks for responding, much of the work I have done reflects on comments on Erik Mona's thread "What would you want from psionics?" or something similar it was posted in 2009. Most players would not want PP to go away, and there needs to be some strong differential for sorcerers or you could just play a sorcerer. Dreamscarred press IMO did not change enough and a complete overhaul ruins backwards compatibility, but could sway people if the powers are amazing. I propose a choice in the middle. I hope you will follow my thread and find you like what you see. I have 3 ideas for Pathfinder Society and will be submitting one soon.