Virgin Air (per CNN and Fox) say it's a false alarm. Homeland Security (per Fox) confirms hijack.
Why the discrepancy?
Listening to local ABC News Radio affiliate... JFK-bound Virgin Air jetliner sent out electronic hijack signal. Pilot now says it is false. Canadian air force jets are escorting the jetliner to New Brunswick, where it will land.
The most shocking part: Canada has an air force. In all seriousness though, let's hope this was just a mechanical error, as the news reporters seem to think it is.