Just a quick post to try out the new WP 2.5 interface ... and also to say it completely wrecked the back-end of the blog since I use the K2 theme to manage some of my presentation settings. I was getting the following error, along with a bunch of other people on t'internet since upgrading WordPress:

Warning: Cannot modify header information - headers already sent by (output started at /var/www/web778/web/wp-includes/widgets.php:1307) in /var/www/web778/web/wp-includes/pluggable.php on line 689

I surfed onto the K2 website and found a blog post 4 days old explaining this was fixed in the latest SVN release. Quick fix was to grab the SVN using:

svn checkout http://kaytwo.googlecode.com/svn/trunk/ kaytwo-read-only

Then trash the K2 directory on my WordPress site and replace the files with the latest and greatest. It worked a treat for me. Actually my sidebar has stopped working now and all of my posts are 'uncatagorised' ... looks like I'll be going back to a default theme for now. I wonder if I can get my catagories back from a backup ...