Just upgraded to WordPress’s new 2.7 software. Looks great as they have totally overhauled the backend and the way you can use the admin cp.
Haven’t tested out all the bugs yet and get a feel for it, but there are a few problems that you should be wary of off the bat. Not all plug-ins work – so before you upgrade, make sure you deactivate all plugins.
For example, the Drop-Down Admin plugin and the Tiny MCE Advanced plugins were not compatible with my 2.7 upgrade. I wasn’t able to access the left side menu on the admin cp (Drop Down Admin must have negated that somehow as when I deactivated it, I found it) and I couldn’t access the “visual” feature for posts (it seems the Tiny MCE Advanced plugin conflicted as well).
I have now deactivated all plugins and will bring each one online one by one in order to see which work.