According to the story, there would be two versions of the iTablet/iSlate/iPad, one supporting AT&T's fast GSM/HSPA network and the other supporting Verizon's reliable CDMA/EVDO network. Both would likely have WiFi and access to associated WiFi hotspots. Verizon's version might also be subject to tiered pricing.
According to a source at Verizon, Apple has been in talks with 'the big red map' to offer the tablet on its robust CDMA network. Additionally Verizon is in talks with Apple to bring the iPhone to its network by late spring or early summer, but specifics haven't yet been finalized.
An iPhone on Verizon makes increasing sense for Apple. At a certain point, everyone who prefers AT&T as a carrier, or is willing to live with AT&T as a carrier just to have an iPhone, will have an iPhone, and for Apple to grow their customer base, they'll need to expand to a network that supports those who want an iPhone but won't got to AT&T for it. The king of that hill is Verizon. Apple has broken exclusivity almost everywhere else. It will have to do it in the US, and LTE is too far out to be a logical change-point.
The rest of the article contains an amusing amount of bickering between the carrier rivals, with AT&T implying any network would have problems with the 7000% data spike that comes with the iPhone.
No matter what happens, we're hoping for multiple carriers, as that would be a multiple win for US consumers.