Now that I'm back from my foray into the sun, I've been able to kick back and take a gander at the psion class. Its a psionic controller that can mess with enemy perceptions, alter memories, and in general do some of the crazy shit that Tetsuo could (screaming optional). I've been a fan of psionics since 2nd Edition, but was never able to use them since every DM I had utterly despised the system because they either didnt own the book, or didnt think that psionics, "had any place in a fantasy game."
I had a bit better luck in 3rd Edition, after convincing one DM that psioncs wasnt overpowered anymore, and got to try out the psychic warrior with some very underwhelming results. I let another player try out a psion that preferred using baleful teleport after locking enemies down in an ectoplasmic wall, since psychic effects could pierce it without any problem. That made it very, very hard to make difficult encounters.
As with clerics and bards, 4th Edition makes the psion a very interesting, balanced, useful class choice. Its definitely more complicated than classes from Player's Handbook, since you have to track power points, but more on that in a bit. As expected, they get to run around in cloth armor, and can use staffs and orbs as implements. I was kinda hoping for some kind of crystal-type implement, like a dorje or whatever, but thats a very simple reskin (and the commentary article supports this notion).
The powers are called disciplines, and they maintain a lot of the older names from previous psion/psionicist incarnations (mind thrust, id insinuation, intellect fortress, etc). Psionic focus seems to be out, but power points are still in, just not used to fuel everything that the class can do (including power-scaling). Instead, you can burn one-or-more power points in order to augment a power, but you can only trigger on augment at a time.
Augmenting your powers is important, because the psion does not get encounter attacks outside of your discipline focus and paragon path: they are all at-will powers that can be augmented to get better effects out of them. For example, id insinuation is a level 3 at-will, ranged 10 burst 1 that deals 1d8 damage and imposes a Fort penalty to the affected creatures. You can dump a power point on this ahead of time in order to increase the Fort penalty, or you can dump two in order to double the damage in addition to tacking on bonus damage if someone nails it with a Fort attack.
Since power points refresh during a short rest, what ends up happening is that your psion has a massive array of at-will attacks that can be boosted up to "encounter-grade" on a limited basis. This is a very interesting way to make them feel different from the rest of the power sources, without overpowering them or making them play by different rules (players of 3rd Edition should remember the "Magic and Psionics is/isnt Different" optional rules). They're definitely not going to play anything like wizards, but arent going to break the game in the process.
Aside from 40+ powers and one build, the debut article also features six feats and a couple paragon paths to go with the whole package. Its not the entire thing, as they are leaving out the "force blasting" build, more paragon paths, and epic destinies, so it feels more like we're getting most of one-half of a entire class. Its technically playable, to be sure, but I think that some magic items and at least one epic destiny would go a long way to making this glass feel half-full.
That being said, its cool, and I'm going to have some fun making a couple psionic characters that I'll never get to play because no one in my group besides me ever runs this show.