Id rather have the 3G version just in case I need it. Plus I would rather have seperate data plans for my phone and the chromebook. If only there were more wifi spots available where I live than I can probably just go with the wifi version.
I would have to have the 3G version but it be best if they also offered an 3G+Wifi Version. It would be a lot better that way, thus at home or wifi equipped school they will allow you to use a wifi connection ! and when out about on a train or whatnot you can use 3g mode!