Diablo 3 speculation has perked up again with Blizzard's splash image teaser. It started with one rune symbol in a mass of ice, and every day they're adding a bit to it. Right now there are 3 runes and the ice is beginning to break.
Fan sites have of course performed the obligatory in-depth analysis of the symbols, yielding some positive evidence. The first one was thought to be from WoW, on the Frostmourne sword to be exact. This may still be, but other sites note that it shares just as many similarites with a Shael rune from Diablo 2: Lord of Destruction. The second one is virtually identical to LOD's Hel rune.
I'm not sure about the third one, someone said it looked like phobos from Starcraft. In that case the image could be showing a rune from every Blizzard series (WoW, Diablo, Starcraft.)
Still, Blizzard's WWI in Paris will run day and date with Diablo 2 and Lord of Destruction's release dates. Here's (insurmountably) hoping they finally pull the curtain on it.