There is an API for it mentioned for Verizons "partners" at this press release:
http://news.vzw.com/news/2009/02/pr2009-02-08a.html I'd suggest emailing on the supplied email addresses for the press release to find out more.
relevant quote:
“The Verizon Hub is an innovative solution to help us all do a better job at managing our busy lives and navigating within our community with point-by-point directions to other contacts’ locations or businesses,” said Doug Antone, president and chief executive officer of Networks In Motion. “NIM’s open ‘Web-to-App API’ allows us to assist our partners in developing features to simplify lives whether on a mobile phone or on the Verizon Hub.”