Block at Last, Once

After several more days of searching Google while logged in and not seeing any option to block, I finally saw it today, once! As you can see from the screenshot below, a search on 'glog' gave me a "block all results from . . ." message for glogster, but none of the other sites listed had the block option. I've highlighted the one I saw and the spot the others should have been. This was in Firefox. I tried several more searches, and none of the results had the block option. When I went back to the 'glog' search, the block option was gone. So I've not had the chance to try clicking on the one block link I've seen so far, but maybe the next one. So is Google slowly moving towards implementing the block option to more users, or do I just get a teaser once in awhile?