The thing to remember is that WordPress is pushing out code revisions and fixes probably very frequently right now (possibly several per hour) to fix bugs and such, so things may be a little unstable for a little bit. Since WordPress has many servers spread out all over the US, the code fixes do not hit every server at the same time. When that happens, things can get cranky until all the servers have the new code and are running it.
When you click on write, or insert image, or manage, or whatever, you connect to one of these servers. The next time you click on a link, it may connect to another server due to server loads. This means that until everything stabilizes, and all the servers are up and running on the same code, there can be some inconsistencies and instabilities.