I have been running WordPress 2.7 since it was released. I have been trying various Plug-Ins, and will try to keep this post updated with any relevant help to those that might be having issues.
I am going to post more, but here is my finding so far.
NextGen seems to give the Admin functions a problem.
Position Yourself seems to hinder the Upload/Insert capability.
Ohz Admin Drop Down Menu causes the left Admin sidebar to disappear.
WP-Amazon plays havoc on capabilities.