After just over 2 years working in IT support, with the CompTIA A+ and Network+ under my belt, I thought it was time to get some Microsoft certs under my belt to back up my experience.
Just in case you didn't know, the MCDST comprises two exams; 70-271 and 70-272. Pass one, and you're an MCP. Pass both, and you're an MCDST.
Don't assume just because Windows 7 is out, that the MCDST is a dead cert either; many large organisations still have and will continue to use XP for years to come and, unlike the newer M$ certificates, the MCDST will never expire (newer certs expire when support for the relevant OS expires).
The MS Press books are the de-facto texts for the MCDST exams. The book is well laid-out, clear, and has few errors. The end of chapter review questions are quite good, though the readiness questions on the accompanying CD leave a little to be desired; they are poorly worded and littered with grammatical and spelling errors. If you're after review questions only, I would look at an Exam Cram book; if it's a good overview of material you want, then get this book.