The suspicion that an announcement will come that day comes via an invitation sent to media for an event at New York City’s Lincoln Center (Frederick P. Rose Hall). There's no detail, except to say it is regarding "the latest news from Verizon Wireless."
Why isn't this an Apple announcement instead of a Verizon one? Well, it's for the iPhone 4, not a new model, with a CDMA antenna. That's not really "big enough" for a Steve Jobs / Apple event. Which, of course, means the hardware will be unchanged, save the antenna, which should be something buyers should think about: since the iPhone runs on annual refreshes, in some 4 - 5 months the iPhone 5 will be here.
While Verizon President and COO Lowell McAdam will be onstage, and although it's not an Apple event, it will be interesting to see if Steve Jobs makes a guest appearance. The event is scheduled for 11AM EST on Jan. 11.