The 2014 WonderCon will be held, like the last two, in Anaheim — on April 18-20. That's Easter weekend.
Last I heard, the convention crew had not yet given up the notion of returning WonderCon to the Moscone Center in San Francisco, and there was a slim hope that dates could be secured to have a WonderCon there later in 2014, perhaps around Thanksgiving. I don't know how much slimmer that hope has gotten in recent months. The Moscone Center is a terrific place to have a con but a difficult place to book. They won't generally book events in the distant future and they tend to favor those that are important cultural events over events that draw a lot of people. No doubt many have argued to them that a comic book convention is both.
Nothing against Anaheim but I hope WonderCon can get back to S.F. some day in some form. It's a great city for a convention and the Moscone offers great facilities. If you can get them, that is.