For me, the best performers of all time on Idol are Kelly C., Fantasia, B., and Adam L.
I was watching a few of their old performances on You Tube and ran across Kelly C's "Natural Woman". Steven T. and JLo really liked Lauren at the beginning. In fact they said they thought they found their winner, but geeze. She didn't even come close to Kelly in either voice or performance. I am a huge Randy Jackson fan, and I'm glad he said something. I think he needed to recognize the different skilll level going on this year from past years to validate the show a bit, e.g. a roundabout way of saying, "yeah, we know our contestants aren't that great this year..."
Sidenote about James Durbin...he really shouldn't be compared to Adam L. because they do different things. However, given their ability to hit high notes long and hard, it's impossible not to. I watched a few of Adam's old AI videos. For me, Adam has a much more deep and appealing tone. However, I actually think James has more range and fluidity.
For me, James and Scotty are the only 2 guys worth much in the top 12. In fact, I think one of these two will win. I think it will be Scotty give that the young girls seem to adore him.