The Neverwinter Nights 2 Player Resource Consortium has released an alpha version for the PRC2 pack. Highlights include the return of Psionics and of Truenaming, as well as all of the PRC Spellbook classes.
The PRC2 pack at the moment includes 126 new classes, 300+ new spells, several hundred new feats, 60+ new races, Psionics, Truenaming, PnP Crafting, Spellbooks, Domains, and a host of other goodies for players and builders alike.

These are most of the things fixed or updated since Alpha 1. There are some others not listed here, because they are minor in nature.