If you have a Blogger team blog, you can now switch the team blog to Blogger Beta, but be warned that the process seems to be a bit tricky, and if you don't do things in the right order the blog may not be converted and may get stuck in "classic" Blogger without the whizzy new Beta features:
If a team member of a blog switches their account to beta before the blog owner does, then the team blog is not converted. It will appear on the team member's dashboard in beta, but clicking on it will lead back to the old version of Blogger. Thus, the blog will still be usable, but without the new features of Blogger in beta (e.g. Labels, Layouts, etc.).
Basically, from the help it looks like the original blog owner has to switch first, and not the other team members. Everyone will also need to get a Google Account, of course.
I guess this means the last holdout, the "big blogs", will be next, and soon. So I really will have to get to grips with the horribly hard looking Beta template code, willy nilly...
UPDATE: I see that Blogger Buzz have now officially announced this switch plus some other news.