The guys at Alea Publishing Group did a bang-up job, and I couldn't be happier with the work.
Mindcraft began life as "The Craft of the Mind" way back in 2001. After seeing the exact same skill-and-feat mechanic show up in at least three different products, I decided to go back to the drawing board and star with something that (1) fits into the way characters are actually created in D&D (i.e., maxing out a few skills instead of buying all of them), (2) reflects "psionics" as something different than magic, in keeping with how it's always been in my home campaign, and (3) is a fun system to play.
The 64-page book contains two new core and prestige classes, with epic, reputation, and "defense" rules included, the necessary mental skills and feats, over 80 mental powers, four new types of "magical" item that are distinct (including one never-before-seen effect that's a great flavorful alternative to an Item of Ability Score Enhancement +6), and a short selection of monsters and sample NPCs. A secretive organization is included, that lets you drop Mindcraft in for a session to try out without needing to re-write your campaign's whole setting.
All that's part for the course in a cap-system, however. The best reason to pick up Mindcraft (in my obviously biased opinion) is the rules. Mental powers aren't the outer-planes magic that the D&D Psionics system is, and it isn't the Force redux that some other "psionics" systems are. The use of any power is an opposed roll using one of three mental skills, with a simple modifier listed right in the power's description. One a character has a mental power, they can try and use that power however many times they want -- although each use imposes some fatigue, which when pushed too far is taken as non-lethal damage.
If there's anything else you'd like to know about Mindcraft, please ask away.