It can do lot more because it's probably more expensive. It's understandable that the lower cost of the Gametrak wouldn't do as much. The only problem I have with PSEye is that it's much than just a sensor, therefore it'll cost much more than a sensor. The sensors in the Wii & Gametrak are minimal by design.
PSEye is pretty much a sensor (for audio, video and image). The logic is in Cell.
As for pricing, Gametrak Freedom costs $70 with the bundled game, $35 standalone. PSEye cost $50 with Eye of Judgment and $40 standalone. No one knows the wand pricing yet, probably similar to Wiimote ($40 standalone ?).
Would be interesting to see who's willing to pick up the package at launch. For some of us. we already have a PS Eye. So the incremental cost should be similar to Gametrak Freedom/PSEye with a bundled game ($50 - $70 ?). For the newcomers. it would be slightly more.
If Sony has gone for a separate ultrasonic sensor bar layout, then it's just playing catch up with Nintendo. It won't make much sense. A business will always build on its strength. In this case, they build on top of their PSEye assets. In fact, we may see even more controllers from Sony (just like Nintendo).
Personally I'm wanting a motion solution that's completely contained in one device: no wires, no dongles, no sensors, no cameras. I want it to have thumbsticks, triggers, 3D positional accuracy , etc & I don't want it have a funny looking light bulb on the end. Evidently there's no company coming close to that. Looks like the closest I'll get is the Wii+. Too bad it doesn't have the 360 games.
Tommy McClain
It probably depends on what game you're playing. The application/content also answers the cost question. For some there is absolutely no need for the thumbstick. For others it's critical. The vendors will have their solutions for these varying needs.
Even for Nintendo, there are games that use Wiimote and the Wii board together, or Wiimote + Vitality sensor, or Wiimote + nunchuck.
And then, there's the thing about "no controller needed":
http://ps3.ign.com/articles/103/1030094p1.html
(See the "Break Out" video)