It's been ten months since Rockstar released Grand Theft Auto IV to rave reviews and blockbuster sales numbers. Tuesday brings a new chapter in GTA IV and a new step in the evolution of downloadable content. While expansion packs that include significant single-player and multiplayer additions are old practice on PC, robust post-market content is virtually unheard of on consoles. Without question The Lost & Damned, a $20 Xbox 360 exclusive, is the meatiest DLC to date. Not only do you get a significant single-player campaign, but L&D includes 54 new music tracks, 20 new vehicles, a half-dozen new weapons, new side missions, new TV shows and new multiplayer modes. That's quite a deal when you consider the three-hour experience provided by Fallout 3's recent Operation: Anchorage DLC cost ten bucks.