At least the guys at WordPress haven’t been sitting back and doing nothing about the horrible host of bugs they introduced with their latest WordPress 2.9 upgrade and have scurried to knock together a 2.9.1 Release Candidate 1 package that addresses many of the issues raised by the new version, closing as many as 23 open bug tickets!
Obviously it might be a good idea to jump onboard at this stage and download and install the release candidate package, which can be downloaded here: WordPress 2.9.1 RC1
Alternatively you could always just wait for the official release to come storming out the doors I suppose! :P
Related Link: http://wordpress.org/development/2009/12/wordpress-2-9-1-release-candidate-1/