Given that everyone at Macworld is publicly reachable via a web email form, I get a lot of random questions in my inbox.
By a wide margin, the two most popular recent questions have been "which Mac should I buy," and "when should I buy it?" After answering the question about 2,500 times (or so it seems), I decided to write up my usual responses for easy future reference. There was some good conversation on the topic in the forums as well; this has become one of the threads to which I point those contemplating the switch.