Rumoured details on the Treo 650 from Gizmodo
Gizmodo has some information on the Treo 650 update. So does Engadget. Pretty much sounds like the rumoured additions will come to be: dedicated answer/disconnect buttons, voice recording, bluetooth, higher res screen (320×320), higher res camera (1.3MP), backlit keyboard, removeable battery, and video-mode on the camera.
Here is a photo with the screen turned on and the backlit keyboard lit up.