At the Games Developers Conference in Cologne, Germany, there is a playable Alpha version of Final Fantasy XIV. Gametrailers has some footage of it, while one of the team members at FFXIVCore wrote up his impressions from playing it for 15 mintues. Gametrailers also has a few more videos that may be more interesting from the game developery perspective, which you can also see from the source link below.
Sources: Gametrailers, FFXIVCore
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