Well, the new Apple MacBook and MacBook Pro has just been announced, so here I want to take a look at what you get in the new MacBook (I will cover the Pro later).
First off the speed bumps, you get 2.1GHz from the base model, and 2.4GHz in the mid-range white and top-range black models. In the black model, you also get a 250GB hard drive, which is a BTO option in the other two. You can also spec up to 4GB of RAM, but this is often a lot cheaper to do after the event from a third party manufacturer (like Crucial). Everything else reads the same, even the graphic card is not a beefier offering. The only other performance enhancing addition, is 3MB of Level 2 cache.
So the good bits are the extra speed and the massive 250GB hard drive option (unless you have a black version). The bad bits, which will be talked about a lot more, is the lack of multi-touch. Apple have this technology and it would be so much nicer if they offered it too the whole range, but I guess that would hurt MacBook Air sales too much, so they will probably wait until a further revision before the MacBook gets this.