Planet halflife reports that GameSpy and Gamespot both have previews of a couple of HL2 levels prior to the whole E3 preview.
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At last, it seems some of the questions are finally being answered, as we had a chance to go hands-on with the game play through a few levels from the game. The good news: the levels we played look like they'll retain the spirit of the original, while at the same using Valve's new Source engine to good use
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Also in other news if you havent yet checked out last year's E3 previews of HL2, you can find torrent's of the videos at steampowered.com.
<sigh>Oh will the wait never end</sigh>