Warhammer: Mark of Chaos - Battle March builds upon the game's tactical foundation to offer new units for each army as well as an original campaign and new online modes. The Xbox 360 version will be a standalone game and also include the original content from Warhammer: Mark of Chaos.

1942: Joint Strike takes inspiration and influence from the 194X series of WWII-themed vertical shooters, but will stand out as its own unique entry in the series. Gameplay will resemble the classic 2-D style that gamers expect, but the game utilizes a full 3-D engine.

Valve's physics-focused puzzle game Portal has been denied access to Xbox Live Arcade according to Valve marketing director Doug Lombardi. Currently part of the Orange Box, Microsoft was approached to have Portal downloadable through XBLA but turned it down due to "size limit and all kinds of other things," although Doug did say it might be possible somewhere down the line, "I think it's a trade-off, we'll see it one day."

SEGA Superstars Tennis is a game that brings together some of the most treasured and well known characters from the SEGA universe, in some of the most unusual courts and outrageous settings ever imagined.

Viking: Battle For Asgard is a hack 'n' slasher where you, as Skarin, get to experience the violent yet spectacular world of the Vikings and their gods.

Ratatouille offers a fresh and exciting take on the platform action genre, engaging players in deep, fluid, and fast gameplay through fun filled mini-games, daring heists, frenzied pursuits and wild chases, providing constant fun and challenge.

Operation Darkness is an epic fantasy WWII turn-based strategy game from Metal Saga developers Success. Set during WW2 you are part of an special ops team tasked with tracking down Hitler, featuring multiple scenarios, mixing historical events with fiction.

Summer Athletics brings sports right into your living room: exciting competitions in over 25 of the most popular summer sports disciplines, such as sprinting, hurdles, cycling, archery, javelin, hammer throw, and swimming, will provide long-lasting fun.

Rez HD is a frenetic, wire-frame cult-classic shooter/adventure backed by industrial beats, taking players deep into the world's computer network, where they must hack the system, alter the visual output and take over the music, creating their own rhythms and eye candy as they dig deeper into the cyberworld.

Risk it all on the expeditions of a lifetime in the card based game Lost Cities as it comes to life on Xbox Live Arcade. Draw from a pool of cards to amass the most points, play your cards wisely, take chances with your money, and create the best strategy to outwit your opponent on the road to victory.

SEGA's combat-intensive RTS Universe at War: Earth Assault for the Xbox 360 will employ a control scheme built from the ground up to ensure smooth gameplay and ease of command for console gamers. Great attention has been paid to implement a balanced gamescape for multiplayer games for console players.

Revolutionizing your control of the five tools in baseball are brand new pitching, fielding and base-running controls and completely overhauled batting interface. Featuring a totally unique trading card mode, robust Minor League system, all-new Signature Style animations for 2008 and more, MLB 2K8 brings a new level of fun to the virtual baseball world.

The basic gameplay is straightforward, familiar, and addictive — just spin a trio of hexes to create a group of three or more matching colors, or build a formation of hexes to create more advanced pieces. Whether you want a relaxing puzzle break or a frantic race against the clock, Hexic 2 has you covered!

Activision announced that Infinity Ward's Call of Duty 4: Modern Warfare Variety Map Pack has set a new record for the number of paid downloads on Xbox LIVE Marketplace, surpassing one million downloads in the first nine days since its release and logging in more than 30 million sessions and more than 32 million hours of gameplay.

Iron Man, an explosive third-person action shooter game that pits one of the world’s most renowned Super Heroes against unspeakable odds, draws its story from the upcoming movie while incorporating story elements from original Iron Man comic books. Iron Man will be downloadable on Xbox Live tomorrow and up on the PlayStation Network soon!

Microsoft announced that European sales have more than doubled in the wake of its March 14 retail price adjustment to an entry-level estimated retail price of £159.99.

Experience the authentic gameplay of “Super Contra” with an updated look and feel by battling through several risky missions either solo or in two player co-op mode, just like in the original.

Yesterday Namco Bandai held its annual Gamer's Day and apart from revealing SoulCalibur IV's release date, it also announced that the original Dreamcast title is coming exclusively to Xbox Live Arcade. As with most XBLA title SoulCalibur will get upgraded graphics, and leaderboards spanning every character and mode, but unfortunately no multiplayer over Live, only local-play Versus mode, as well as standard Arcade, Training, and Survival modes. Currently scheduled for summer 2008 release.

GripShift combines automotive and puzzle solving skills across 120 challenging levels, 25 rubber burning race tracks and 20 deadly deathmatch arenas across four themed worlds.

Microsoft and Bungie once more continue the fight as it has just released the next wave of Halo 3 downloadable content on Xbox Live Marketplace for 800 Microsoft Points. The 410mb Legendary Map Pack introduces three new maps to the title’s multiplayer experience, Ghost Town, Avalanche, and Blackout!

Rock Band allows you to perform music from the world’s biggest rock artists with your friends as a virtual band using drum, bass/lead guitar and microphone, in addition to offering online connectivity. Last week EA finally revealed that it would be releasing Rock Band in Europe on May 23, but only on Xbox 360 as Microsoft scored a timed exclusive. Apart from the pricing outrage (inexplicably the bundle in twice as expensive) it turns out PS2, Wii and PS3 gamers will have to wait until August.

SEGA's Universe at War: Earth Assault, developed by Petroglyph, is a combat-intensive RTS game enlisting players in an epic struggle to prevent total alien domination of planet Earth. SEGA has released a 545 mb demo that features Novus and the Hierarchy, two of the three factions you can play as in Universe at War: Earth Assault!

A sequel to the original Xbox title, Ninja Gaiden 2 has players once again assuming the role of Ryu Hayabusa as they guide the ninja hero on a quest to avenge his clan and prevent the destruction of the human race.

SEGA's Condemned 2: Bloodshot is a first-person action thriller immersing players in a world of psychological terror, featuring all-new fighting mechanics and online multiplayer functionality.

Toshiba may have conceded in the HD war, that doesn't mean Microsoft will throw in the towel, even if its only with a new firmware update for the Xbox 360 HD DVD player. Log into Xbox Live and put in a HD DVD disc, you will automatically be prompted to update (adds support for network features and improves compatibility).