for those who planned to take MCSE, please pick 2 MCTS exam for your MCSE cert. You can do that. You'll save your upgrade path if you take 2 MCTS exam for your MCSE

The MCTS exam you can choose is for your client OS exam i recommend windows vista, and for your elective exam you can pick windows 7. Both are MCTS paper. But you already meet the requirement for MCSE cert. As you know, both paper are easy and pretty much the same. You don't have to study much to pass this paper.

Basically those who have MCSE now, also have MCTS in client OS.