yes, they are closing or being sold. When, I have no idea. It was mentioned in the December issue of San Diego Magazine at the very end of their restaurant column. I think Seibert is going somewhere else to cook, I forgot where, but the article mentioned it. I recall something about "J and C," for what that's worth.
Here's the quote from San Diego Magazine
Coming soon to a restored Art Deco– style building at Seventh and C downtown, Jade Theatre will offer dining and lounging on three floors, with the Jason Seibert–led Jade Restaurant as its centerpiece. The talented Seibert, who perhaps has a better nose for culinary innovation than choosing locations, will sell or close his pleasant but underpopulated Café Cerise on Sixth Avenue.
Josh, why not give chef Seibert a call. That would surely be more authoritative than whatever rumors we may be able to pass on.
We all know that Cerise's problems had zero to do with the food and everything to do with the poor location. That whole part of downtown is full of parking structures, but every one of them is locked and fortified by 7 p.m., so dining at Cerise, for us, always entailed a walk of several blocks over broken sidewalks, through a neighborhood nearly deserted by everyone but the homeless and delusional. Nearby establishments that appear to thrive (La Gran Tapa comes to mind) seem to feature an appealing bar scene. If Jason Seibert does close down, I sincerely hope he'll try again.