I just rewatched there to check... after the Doctor and the Master sent the time lords back to the time war, the Master just seemed to just disappear, and no- one seemed to notice. At least when he reappears in due course we won't need a convoluted way of bringing him back....

For what it's worth I enjoyed tonights episode, it was better than part one. It was fitting that the doctor went back to see his former companions, which was a tribute to DTs contibution to the show as much as anything else. Matt smith looked like he was enjoying himself...roll on spring 2010!

He seemed to head back into the Time War with the other timelords and John Simms seem to suggest as much in DW:C. So there is some rotten eggs in one baskets awaiting a comeback.