According to WoTC, players love the new"ish" psionics rules and now they've come out with incarnum.
Do players and DM's really care for all of these new rules? Honestly, I've played with a few DM's and briefly DM'd myself and not only were psionics not used, but they were discouraged.
I know the most likely answer is that WoTC is just introducing new content to sell books, but I'd like to know what the players and DM's really think.
My opinion is that incarnum is just complicating things more than is necessary and that to add it in to a world like the Forgotten Realms is just silly. Hell, I don't think it was even included in the brand new Eberron setting (I haven't bought any of those books so I may be wrong).