Microsoft this week unveiled a host of new games and features for its Xbox gaming console and online gaming service, as well as new offerings that aim to make Xbox the focus of home entertainment centers.The new games and upgrades were announced in Los Angeles Monday in anticipation of the Electronic Entertainment Expo (E3) which begins Wednesday.Microsoft said that by the Christmas holiday season more than 50 games will be available for its Xbox Live online gaming service and more than 100 will be available by this time next year. New games will include "Halo 2," "Conker: Live and Uncut," and "Grabbed by the Ghoulies" by Rare, which Microsoft acquired in September 2002.Microsoft launched Xbox Live, which allows users to play with other gamers via a broadband connection, last November and the service now has a community of over 500,000 gamers, the company said.While the new games are aimed at expanding this community, Microsoft's key emphasis Monday was on the expansion of gaming to include other digital entertainment and services. In this vein, Microsoft said that it plans to launch an Xbox "Music Mixer" for the Christmas season which will allow users to share photos and music and access DVD and CD playback. Music Maker will debut in the U.S. for $39.99.Availability of the new games in Europe will depend on the title, said a spokeswoman for the company in the U.K. Music Mixer is due out in Europe after its U.S. launch, but no specific date or price was given.Microsoft also previewed XSN Sports, a lineup of Xbox games in which users will be able to create their own virtual leagues and competitions. Users will be able to access XSN Sport, due to roll out in August, using an Xbox, the Web or their cell phones.Microsoft is also planning upgrades to Xbox Live that will be made over the next year, including alerts that can be sent to users' cell phones, PDAs or via MSN Messenger, and voice chat for organizing games, as well as new teams and competitions.The spokeswoman said that more Xbox announcements are due out this week during E3, which runs through Friday. More information on the show can be found here.