I became MCAD certified last week - after about 8 months of MSDN/book studying - woo! :)
I don't know if this goes for the rest of the world, but here in the UK, theres a bit of a stigma associated with the MS exams.... "it shows you have memorised the MSDN documentation on subject X, but it doesn't show how good a programmer you are"...
I've heard about all the 10-year olds that have managed to get MCAD, and it is completely true that MCAD certification (or any other Microsoft programming certificate) does not confirm your uber-programmer status. You could have every MS certification under the sun and still know nothing about how to refactor a dodgy bit of code, or how to structure your code well for the best possible re-use.
That said, I definitely believe that there is a lot of value to this MCAD lark. It shows that you know about and have studied key MS technologies. Employ a MCAD programmer and you can be assured that the programmer at least knows about the options for separating a web app over multiple physical tiers, even if they never actually needed to do it before. The word "knows" is emphasized for a reason - that 10 year old kid who got MCAD in 4 weeks for the hell of it is going to know a lot less than the experienced developer that didn't have to do much studying because he/she knew most of the stuff already. I guess that's why theres a stigma - the MCAD doesn't differentiate between the kid and the experienced developer. So, while I think its definitely a good thing to have, its nothing without knowledge, and proven experience in .NET and software engineering in general.
Now, onto the .NET 2 exams... :)