I just took the 70-461 exam and passed.
Concerning the 2012 Certification book, yes, the practice questions there are easier than what's on the exam.
However, with respect to the 2008 Certification book, I thought the 2008 practice questions were harder than the exam questions.
Point here being is that it might not hurt to pick up the 2008 Certification book.
Myself - I have three years experience with SQL development. Like Microsoft, I wouldn't recommend this exam to someone with less than 12 months application experience. That would be cruel. Nevertheless, there's a lot to be learned from the certification books.
My best advice is to look over the book and ask yourself what areas do you have experience with and what areas you do not. For instance, my work experience has me working with XML techniques, cursor vs. while loop decisions, temp table vs. table variable, and Dynamic SQL experience. Not to mention, I like reading up on performance and tuning techniques.
No, I'm not a guru, but as mentioned before, these are the areas that I do a lot of work with.
However, my work experience has me falling short with Schemabinding methods, Instead-Of triggers for Views, and error handling. So yeah, these were chapters that I applied a little more focus towards.
A good study plan would be knocking out a chapter during the weekdays and one chapter on the weekend.