The first maintenance release for Wordpress 2.3 line is out for beta test using wordpress 2.3.1 version. Got this information from Boren Blog, Some information on bug fixes

* Tagging support for Windows Live Writer
* A login bug that affected those with a Blog Address different than
their WordPress Address is fixed
* Faster taxonomy database queries, especially tag intersection queries
* Link importer fixes

You can download this beta release here.

If you are using 2.3 line version, you can try out this beta maintenance release.