If you've been updating your site through Subversion to get the bleeding edge code that isn't even tested completely and could be unstable you should stop right now. Trunk is going to get a lot more unstable shortly as I merge in WordPress 2.7.
If you do want to update from Subversion, a better solution would be to follow the 2.6 branch. This is the code that releases are currently built from and receives bug fixes first.
