After a week long tease by Blizzard, Diablo 3 has just been announced in Paris. The splash screen has been updated at their homepage and The Escapist has the first write-up."
While there aren't many details available yet, it is known that Deckard Cain returns to help our heroes yet again.

http://games.slashdot.org/article.pl.../06/28/1134227