The Murlocket is probably my favorite reference, because rggglrlllrrlrlrlrl. Of course, other community personalities show up in Diablo III. Expect your world-saving adventurer to encounter Zarhym, and you'll take some spoiling vengeance out on those pesky Dataminers. We also find out what happened to the Lich King's helm after all that fuss in Northrend. It's sitting in a cave in Act III. No wonder it was such a mystery.
Check out our buddies at Wowhead for more WoW references in Diablo III. We're certain plenty of additional WoW references lurk in the dark corners of Diablo III, and we'd love to see them all.