From the post linked above:
"This is because buying a new bike is like sex in that it’s impossible to get right the first time. Nobody can tell you how to do it. You’ve got to make your mistakes yourself.
Of course, if you’re considering a new bike purchase, you should do your homework, you should ask people for advice, and you should shop around. But you should also realize that since you’re not a cyclist yet you haven’t learned what kind of cyclist you are yet either, so you don’t know what kind of bike you need. Just jump in, buy what you can afford and what makes sense at the time, and try to ask a reasonable price when you put it on Craigslist six months later to buy the bike you now know you need."