Author's Saving Throw: The writers made a few attempts to rein in their more absurd twists and turns, such as removing Alice's story-breaking super powers and clone army, and quietly ignoring the ludicrous, virally-induced global drought from the previous film. If they succeeded or not is up to debate.
Broken Base: Should have the clone army received more screentime? Some think it was good to remove it, while others would have wanted the plot to use it for anything better than a gigantic Sacrificial Lion.
Ear Worm: The opening theme has been known to induce random audience head-bobbing.
Hilarious in Hindsight: The character Crystal Waters is an actress before the Zombie Apocalypse. The name sounds unintentionally a nod to Clear Rivers from Final Destination 1 & 2, portrayed by Ali Larter who portrays Claire Redfield.
He's Just Hiding: Before the release of Resident Evil: Retribution, fans speculated that Wesker survived the helicopter mini-nuke at the ending of the movie. This is supported by some eagle-eyed viewers noticing a parachute opening in the distance when one of the characters revealed himself to have survived. Wesker's survival was later confirmed by a press release for Retribution.
Claire backing away from the Executioner looks like she's breakdancing.
Take That, Scrappy!: Alice gets brought down to normal, ends up on the receiving end of a Curb-Stomp Battle and has all her clones wiped out. For many, it was considered to be the best thing that the directors did to try and redeem the films. But since Alice is improbably overjoyed by it, is still the only character to actually do anything, and remains somehow still capable of doing rather ludicrous stunts even without superpowers, it's ultimately kind of a moot point.