After reading more of it...I think that the Expanded Psionics Handbook is a 500% improvement over it's last incarnation. With the way powers scale and their more general nature, I can see them easily capable of replacing magic as the default preternatural power set. The various energy powers are flexible in the type of damage that they do, and they range from bursts, to rays, to touch attacks, and more. I see the Kinetisist as being a potentially better blaster-type than a Sorcerer.
The most unbalancing thing that I have seen is the new creature called the Unbodied. This creature is stated out for use as a PC race at the end of it's entry with only a +4 level adjustment. It has a metric F*** ton of innate powers, stat increases, 4 racial hit dice (+feats and skills), and it's considered a 4th level Psion (Telepath) for stacking with class levels. Unbalanced or not, who wouldn't want to play Saint Jack the Bodiless?