Ah...now sadly this has been confirmed: Dave Arneson has indeed passed from our realm and on into the next. Farewell captain! You shall be missed. More here.
Huzzah! It has come to light that the initial report of David's passing had been greatly exaggerated. So...Please ignore the rest of this erroneous post.
Dave Arneson, co-creator of Dungeons and Dragons, creator of the Blackmoor campaign setting (longest running campaign at 30+ years) and overall gaming enthusiast has passed away today. He was one of the last of the "old guard", the progenitors of this hobby. His contributions to the hobby were insurmountable.
For more information: Original D&D Discussion
Dave you will be remembered, and sorely missed. RIP 1947-2009
16 minutes ago