Comes with a larger drive standard and more RAM standard.
Unless they got held up with the new model and are going to push it out a month later, and the spec boost was just temporary. But that would be bad marketing and would piss off quite a few people to update a product then update it again 1 month later. Again they could do this, they did something like this before with the iPhone and gave old users in store credit.
Also if you want to wait for a new design you can pretty much say goodbye to a matte display unless you buy a current model.
The next lot of chips from Intel is due out in April, with mobile Nehalem chips coming a few months after, so possibly no update until Q3 2009.
I'd cut your losses and buy the 15" Macbook Pro, most of the owners on here say that the screen is far better than the old matte screen. And for things like colour correction etc. Notebook screens are crap, be it matte or glossy.
The 2.4ghz 15" + a 20" Cinema Display or S-IPS Dell Monitor would be an excellent buy, and would save you $200 and give you a FAR BETTER screen for Final Cut.