You can spend $179 to save that $1.99. That 11n Mac isn't going to do you much good without an 11n access point. And Apple has a deal for you. It's their new Airport Extreme. Supposedly, included with it is the very same $1.99 upgrade software.
Actually, the features for the device look good on paper: network printing and network storage. But so far more buyers are unhappy than happy with it, at least the buyers who are posting.
Apple Charges Fee for Hardware You Already Have