not to be rude, but 60inch plasma doesn't tell us anymore than 4door car.
there's a reason some plasmas cost 600bux and some cost 4k. give us some details on what you bought, and what the source is, and perhaps what you're comparing it to as well(as motion on a 40inch will always looking better than on a 60inch, all else being equal) and maybe we can point you in the right direction.
Displays: Samsung PN64F8500/JVC X35
AVR: Pioneer VSX-1130K, 7.1/5.1.2 audio
Sources: HTPC(Enby), PS3, XBOX360, Wii
Control: Harmony One