It supposedly fixes about 20 known issues from the recent 2.3 update and will likely be well worth taking a look at.
As cool as the changes in version 2.3 were, it presented quite a nightmare to those that attempted upgrades without doing much research.

Many old plug-ins were broken – more than I can even believe, but it did force me to evaluate all of my own installations, both for myself and for clients, and two people are now making the rounds doing all of the upgrades for all the software as well as all the plug-ins,

Stay tuned for further notice on an actual release of 2.31, and if you’re brave enough (I’m not)  install the RC and tell me how it is

The original post is titled WordPress 2.3 RC1 , and it came from Get WordPressed .