Blizzard realizes if you give a mouse a Legendary cookie, he's gonna want more Legendary cookies. So, "due to the overwhelming popularity" of last week's birthday buff, Diablo 3will retain the doubled drop rate for Legendary items even when the buff ends today. Huzzah!
That's for PC and Mac versions since that's where the buff was introduced, but we expect that'll probably change once the console clamor kicks in. Who knows how high the rate will be when Diablo 3: Reaper of Souls hits PS4, Xbox One, Xbox 360 and PS3 on August 19?