Panda is an experiment that seems to be failing. But it's been set free and it's calling the shots. The two questions now are:-
1) Will Panda ever really learn to discriminate between good and bad sites/pages (because currently it get's it wrong a lot)?
2) How long will google stick with it before there's one less giant Panda in the world?
Google may well congratulate itself over what's been banished from the SERPS (article spam). But, that's only half the picture. They surely can't be happy with what is in the SERPS these days?!
I see article spam + false positives (that are actually good sites) replaced with... well... junk.