The Walmart Gamecenter allows users to try out demos of at least two games: Mass Effect 2 and Dead Space 2, without any intermediary ads.
The new services was discovered and reported on earlier by VentureBeat.
Gaikai's service detects if a user has an acceptable connection, and, if so, will display the option to play a game, VentureBeat reported. That seems to be true; when I accessed the site via Chrome over a VPN, I was offered the option to view videos about the game. When I tried again with Internet Explorer and my own connection, the offer appeared.
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