There is always something better around the corner, but I don't think price drops are likely. Since even the MacBook Pros didn't get an upgrade yesterday, I think the MacBooks won't see any changes for a while. There's a chance that Apple Expo Paris next month could bring upgrades across the board (iMacs, MacBook Pros, MacBooks, Mac minis), but that's out of your time frame and the MacBooks would be on the lower end of probable models to see the updates then anyway.
I think you'll be fine to go with the current system with the coupon.