Actor Allusion: During a chase scene, after the top of Triton's car is sliced off, one of Rome's henchmen comments that Triton is like "The Terminator". Rome (Played by Robert Patrick, who played the T-1000 whose truck gets its top sliced off during a chase scene in Terminator 2: Judgment Day) glances at him through the mirror.
Randy Orton was going to be in the third film, but real life marines didn't like that due to his history in the marines, and the role went to The Miz, CM Punk was also in the talks for the role.
There are already talks of ''The Marine 4'' which would have featured Eve Torres, but this obviously had to be scrapped when she left the company. Marine 4 is still slated for release in 2015, but a press release showed that it will feature the return of the Miz's character from the third movie, although it made a point to add it would also feature Fandango dance partner Summer Rae, so the "female Marine" idea might still be on the table.