Just so that my iPod Touch can add the most standard of apps?
If that is the case I might as well just stick with all the web apps that I can use, but then of course I have to be on a wifi network to use them.
But really? Will having mail, weather, stocks and maps make that much of a difference?
Nah, I don't think so.
Plus, the $20 is only if you have a unit already; if you go buy one it will come included.