Verizon's promotion of double data caps for its 4G LTE customers took everyone by surprise — we've become accustomed to seeing buckets shrink and move away from unlimited for a couple years now. Of course, there's a perfectly good reason behind the promotion: speaking at a conference yesterday, Verizon CFO Fran Shammo noted that the deal is designed to incentivize subscribers to move into its LTE network to make more room for the iPhone, which is a notoriously data-intensive device that tops out at EV-DO (for now, anyway). Shammo also said that he wants to "make sure" he doesn't have to add any additional EV-DO capacity to accommodate the iPhone — a wasted investment, considering everything is moving to LTE in the long term — so freeing up 3G capacity with a nice plan deal is a creative way to go.

Though Verizon's EV-DO service is generally slower than AT&T's HSPA, there haven't been any widespread complaints of the network grinding to a halt as there have been on Sprint — so for now, Shammo's move would appear to be a proactive one. Better to plan ahead, of course.