Did you happen to take a gravity reading before you racked them? It definitely looks like the one has started fermenting again, but its hard to say why. If they weren't finished before you racked them, you probably just stirred up some yeast and they kick started. It could also be an infection, but its not a sure thing by any means. Watch it and test the gravity, see where it finishes up at and taste it along the way, that will tell you if anything is wrong. Also, how much yeast did you add? That might tell you whether they stalled out before you moved them to secondary.
Also, if I'm reading it right the picture is of the beers after moving to secondary? If that's the case, there's an awful lot of headspace in the two on the right. If they're still fermenting, which it looks like the yellow one is, then its not a big deal since the CO2 will move off some of the oxygen and the yeast will soak some more up. If the other one isn't fermenting, though, you've got a good deal of oxygen in that carboy that might lead to some troubles. Just something to keep in mind in case they start to taste off, so you can quickly drink the rest before they go!