The 70-175 format is the same as most other exams. The only case study exam I am familiar with on the MCSD side is the Solutions Architecture exam. You will need experience. I also recommend the Transcender prep test for this exam - it's what I used. I am an entry level VB programmer and am currently doing QA work.
Experience is best.
You'll definitely what to buy a good book, and perhaps invest in prep tests as well. For me personally, the 70-100 exam was the hardest exam that I've taken. So I wouldn't worry too much about the current exams retiring anytime soon. I do, however, believe that when the .Net exams come out they will be much more difficult than the VB6 exams. Yes, I think there are a LOT of openings where those credentials can get you a good job.