I've been studying for around one month (27 days to be specific), took three days off last week and went for a vacation which was really a BIG HELP .
I didn't like this course at all and I don't really understand the point of calling it Application Infrastructure and to have exam for it seems like a waste of money/time for me but it seems MS want to get our money at any way.
This is the first exam I took that I use only one book for it The MS Press one because I didn't read positive reviews about Sybex book. I did get Windows 2008 R2 unleached book not a long time ago but I havn't read it thoroughly.
I have to say as well that it's very confusing to read the book which uses all old terms (like Terminal Services) while at lab it's called something else. My lab has 3 machines 2 Windows Server 2008 R2 and one XP machine in addition to my host (Win 7) which I used to test IIS.
I did a good thing by taking 70-646 first because I've already studied 4/9 of the book's chapters so I really recommend every one to take 70-646 first (if you're planning to take MCITP-SA) since it will be very helpful and it will cut study time.
The section I found hardest to study was IIS, I'm very unfamiliar with it and I didn't really use it much. I think it's my weak point. Other chapters were just fine not really that hard to study/lab.
I will finish reading today and tomorrow will do a practice test, well I think I've talked a lot but I'm really bored It wasn't really joyful to study for it unlike 646 which was challenging and fun.
Anyway wish me luck, test next Thursday 1:00 PM @ Beirut. If anyone took this test I appreciate last minute tips

P.S:I will study till 2:30 AM then gonna see Celtics Vs Miami don't know yet how in the world I will wake up to work tomorrow