I'm not sure if Red Hat's decision to join forces with CentOS will turn the whole FOSS world upside down, but as a chess move, it is quite an interesting development. You might say it is one of those events that seems unexpected when it happens, but when you look back, it seems inevitable.
Pardon my surprise, but seriously, less than a year ago, I was sitting in an editorial meeting pondering whether we could safely advertise a CentOS DVD as being "based on Red Hat source code" without getting sued. And by the way, we've never had a Red Hat Enterprise Linux DVD. Why? Because no company that makes its livelihood selling a product wants to see someone else give that product away for free.