The scene in which Claire and Leon meet, is a reenactment of how they met in Resident Evil 2. In the game: Leon runs towards the diner and sees Claire being faced off with a zombie. He say's "Get down!" and shoots the zombie. Claire then looks at his face as he offers her his hand. In the movie, Claire goes off to look for a survivor that she hears running around, she looks out the corner of a wall to hear Leon say, "Get down!" He shoots the zombies and offers Claire his hand as she says, "Leon!"
WilPharma is the corporation responsible for the biohazard in this movie. WilPharma is also Umbrella's replacement and stole the G-Virus sample and research from Umbrella after Raccoon City's ultimate destruction.
This the first Resident Evil movie to be in CGs (computer graphics), and is also the first Resident Evil to be based directly off the games, and not an original right up like the live-action movies were.
Like in the game, the CG movie comes with an entire arsenal of new and old but familiar weapons. Leon uses the same USP .45 with laser and tactical illumination as the one he used in Resident Evil 4, along with a Glock 26 for backup. The senator's bodyguards used the standard Glock 17 handguns when they shot the first zombie in the airport terminal. The standard weapon used in this CG Movie by SRT units, the soldiers and once by Leon to bring down the bridge on top of Curtis' monster ego, with the exception of Angela who uses a Custom MP5 and a Glock 26 with a compensator. The weapons used by the bad guy, Frederic Downing, is a Walther PPK (seems to be a British favorite). The airport security guy with the MP7A1, depicted in the Trailer being attacked by a zombie was nowhere to be seen in the movie.
At the very end of the movie, before the credits roll, the company Tricell (Umbrella's replacement and merger) is briefly introduced, looking for any remains of the G-Virus. Tricell is more known in the next Resident Evil game, Resident Evil 5.
After the time bomb goes off, Claire Redfield goes up the elevator to the control room. We can see a monitor on the right of the screen which resembles the single open eye motif used at the start of the first Resident Evil game.