I use my 15" MBP as my primary machine. The only limitation I have found is when playing high graphic intensity video games, otherwise my MBP works great as a desktop replacement. Don't worry about overheating. If it is sitting on a desk you will not notice the overheat issue.
By the way, congratulations on getting your first mac.
Thanks! As for me, I don't do any gaming so that should solidify this purchase.
Let the countdown begin!