GameStop's website currently lists the peripheral at $24.99, five bucks over the price announced this morning. The retail listing uses an image matching the new appearance of the device (inside a new, larger Wii remote jacket), suggesting that GameStop has had time to update the price to match Nintendo's announcement -- but hasn't. Of course, there is a chance this isn't GameStop's final price.
If you don't mind waiting, Gamestop is taking preorders of the Wii Sports Resort/MotionPlus bundle for the recommended $49.99 price. If you do mind waiting and you don't want Resort, then ... go pretty much anywhere else.