I've been studying for the SQL 2012 Certification and sitting the beta exams. I've done the first three DBA exams now with one to go later this week. 70-461, 70-462 and 70-464 all done, with 70-465 as the one I'm yet to do.
Anyone can sit the beta exams but they finish up this week, you can see details on them on the born to learn blog. While I've sat the 'administration' streams for SQL 2000, 2005 and 2008 I'd never done a beta exam. You don't get your results at the end of the exam session, they send them out sometime before the exam goes live
So far I've found the developer strain to be a bit more challenging and the administration exams to be pretty straight forward. Guess that shows where I sit skill-wise, I certainly do a lot more DBA work than development. The whole thing has been thoroughly enjoyable though.
My first real exposure to SQL 2012 was attending Greg Lowe's What's New in SQL Server 2012 course in February. Since then I have been pretty busy reading, testing and trying it out. If it turns out I pass all the beta exams, then I'll look to do the BI ones too, though that will be a real stretch since it looks very much focused on BI Developers rather than the infrastructure side.