Yeah..and the radio-less internet tablets were just amazingly popular with the average joe before. You have it backwards..having a cellular radio makes it more appealing to the masses (single device that does everything), thus attracting larger numbers of customers...thus encouraging economy of scale and finally helping to keep costs down.

A "modular" N900 with removable/detachable radio would likely cost as much or more than the N900 we have now...without the radio. Modularity, as has been previously mentioned, adds enormous costs to development and manufacturing. Just having a removable battery adds to those costs in a non-trivial way (just ask Apple).

If there is enough demand, perhaps Nokia will release a true "tablet" follow-on, but given the relative commercial failure of the N800/N810 by comparison to their phones...I wouldn't hold my breath.