Most labs running replication or validation studies probably did not get started until November-December 2009, some are probably just starting now. A good study takes several months to plan, collect, test, evaluate and write-up. Then they have to go through the peer review process and then wait for publication, which takes several more months, for a fast journal anyway. If there are problems with the article, the peer review process will take longer (six months to a year), if there are no major problems, the article can be peer reviewed and approved in a month perhaps.
So my guess would be at least six months from start of study to publication in the best case scenario. Therefore based on the starting time, we could get a nice group of studies some time early in the summer. One or two studies here and there are not enough, 8-10 studies that generally agree start becoming significant in a statistical meta-analytical sense. So IF we get that many studies that agree, and IF the best case timeline works, there might be a preliminary answer early to middle summer. But if there is more debate, it could drag on for months, years, even decades.
However, the studies will appear singly, and probably be analyzed individually by everyone, so we may have some reports before summer.