Ricky Gervais and Katt Williams both did full motion and voice capture for their brief appearances in their own comedy skits at the Split Sides Comedy Club and on the in-game television.
The first Grand Theft Auto game to feature ragdoll physics, dynamic lighting, realistic water physics, realistic object physics, and realistic NPC/World interaction.
When voice actors auditioned for their roles, they were told they were auditioning for a fake game called "Frozen".
The character Niko Bellic is based on Vladimir Mashkov's character from Đằng Sau Chiến Tuyến (2001). Mashkov was offered the role (voice), but turned it down because he didn't take it seriously at the time, as he explains in the talk-show interview Vladimir Mashkov (2010). This is parallel to how Michael Hollick stated he was only hired for the motion capture and later hired for the voicing two weeks afterwards.
With an estimated budget of $100 million (US), it held the record for the most expensive video game produced at the time of its release.