In one of latest Blizzard videos about Blizzard Arcade winners, we can see one new developer... well, not new, but if you played or just read news about currently cancelled F2P Command & Conquer, you will know that guy.
Tim Morten, who was C&C F2P (previously known as Generals 2, now cancelled, was only playable as Alpha) senior development director, now is a Lead Game Producer of SC2. Tim Morten does not correlates at all with C&C4, which was fail as we all know.
In my opinion, new developers can bring us some new fresh ideas to the game. So I think this is really good news that Tim Morten now is working on SC2. Also I want to remember you that Dustin Browder was one of Red Alert 2 developers. And also I want to remember you that fresh blood helped Diablo 3, when Jim Mosqueira joined D3 development team.