My advice to you is to wait. I had to wait 3 years before I got my first Mac! Once the chance finally came, I snatched it up as fast as I could. I knew there were rumors of Apple releasing a new MacBook 13" soon but I figured I better take my chances. It was a graduation gift from my family and if I didn't take the deal, it would possibly mean waiting more months before I could get it.
So I get the MacBook 13" Aluminum Unibody and what do you know, 30 days later Apple bumps my version up to the MacBook Pro 13", improve the specs and they even lower the price. You can't imagine how pissed I was at myself. Every time I saw a MBP 13" in public it would remind me of my mistake. Anywho, I ended up selling it to my sister a year later and I purchased a new i5 MacBook Pro 15". I actually had enough money before the new MacBook Pros came out in April 2010 but I knew there were new ones right around the corner. I'm glad I had the chance to own this computer from the beginning of its product life cycle.
And as other people stated, Apple does charge restocking fee's if you return it, so you should just hold off or buy it. If you buy it now my guess is that you will have 4-5 months maybe before Apple bumps the specs. Keep in mind that waiting longer only means that by the time you get the computer, it will be better than what you would of gotten if you didn't wait. If I got that MacBook the day I wanted it first 3 years before I actually got it, I would still be using a base line white macbook running tiger with 2gb of ram and a horrible processor haha.