Should i get a macbook now?<possible 20 points>?

I have 3 days till the deal is over (free itouch) and i was wondering should i get a macbook or should i wait till a new macbook comes out?? About how many years do they usually make a new macbook?(im kind of worried that ill buy it and in like a month theyll make a new macbook[ like the ipod nano]) Also is there any other good deals on good laptops with a good webcam for aim? And is there any weaknesses of getting the black one (because thats the one i want) or should i get the white one?(price isnt that big of a deal) Thanks so much!