Good news, everyone: the migration to PStudio is complete! It took about twice as long as I had estimated, so I’m right on schedule (in engineering-time).
Before you go tearing off to check it out, please, I beg you, finish reading this post and read the documentation.
Here’s where things stand tonight (Sunday 20/12/2009):
We’re going to leave the old systems locked down for the time being. But consider the code-freeze tentatively lifted on the new system. Everything should be good-to-go in PStudio, but there’s always the chance we’ll discover some horrible screw-up over the next few days that would force us to roll back. So you might not want to do a whole lot of work that you’d be sad to loose. I imagine that after a week or so of burn-in time, we’ll have discovered any major flaws. We’ll be working to delete the old data and set up redirects next week.

Hopefully, you’ll find that your accounts from the old systems were moved over intact. However, if not, you can use the “forgot password” feature to get a new password, or just sign up with a whole new account. This system is running on it’s own, internal Crowd database, so what happens here won’t affect you accounts on any other Atlassian Systems.
Read the documentation to find out more about user management and how to make sure you’ve got the correct permissions to work on your project.
There will definitely be some manual clean-up required. You can find out what to look out for by reading the documentation.
And lastly, read the documentation. Now go check it out:

Welcome to Plugins Studio!