Bornakk announced today on the general discussion forums (why he didn't do this on the tech support forums, I don't know...) that they are having a number of realms randomly drop people. Indeed, this happened to me over on Eldre'Thalas this morning.
If you are having issues, remember that you can go to the Blizzard's tech support forums and ask a question there. You can also check out our guide for solving all these connection issues, if Blizzard doesn't come through with a solution for you.
We'll keep you updated on this weekend hiccup – stay tuned to WoW Insider for the latest!