Update 2012/07/13 - Still happy I was wrong, wrong, wrong about this.
I'm not a SCOTUS watcher, so any prediction I make on the PPACA ruling due this week is a WAG. Nonetheless, based on the political nature of the case, rulings handed down last week, and the general trend of conservative actions over the past decade, I think the ruling will come down as follows: 5-4 to overturn the mandate, 5-4 to overturn the Medicaid expansion, and 6-3 to uphold the rest, with at least one concurrence on the 6-3 ruling.
Update 2012/06/25 - I'm not changing my prediction, but the speculation by commenters at BJ that Scalia and Alito blew their cool today because the PPACA will be upheld on Thursday seems reasonable. I hope they are right and I am wrong.