Near the end of the movie Zev Guttman gets out of a cab with a bag in his hands but when the cab pulls away, there is no bag.
the DVD cover shows Plummer holding a gun with a hammer and safety (such as Beretta). He only uses a Glock 19 in the film.
The security guard pulls the pistol out and asks if it's a Glock. The Glock design is very distinctive, and unique; so anyone who knows what a Glock is doesn't have to ask. Also, "Glock" is engraved on the slide.
On the train to Philadelphia, Tyler is seen playing a Playstation Vita but when Zev grabs it from him, he calls it a PSP.