All three helicopters (2 black, one white) are Eurocopter (nee Aerospatiale) AS-350 Ecureuils (Squirrels). The N-numbers were all sequential as well - N350SC, N351SC, and N352SC.
In the scene where Nicolas Cage is zapping through TV channels, he stops at one showing the movie Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb (1964), leaving it on for the FBI to listen to. The plot of "Dr. Strangelove" is about a rogue general attempting to start a nuclear holocaust with a wayward nuke. An obvious reference to the nuke in Next (2007).
The terrorists communicate in French and speak English with a French accent. But when the sniper misses his shot, he curses in Serbian.