I measured the input lag of a few displays tonight. I brought my laptop into a store and connected it to the displays using HDMI. I put each display into "Game Mode" when I could figure out how to do so. I don't know if these delays are absolute, since I was only comparing the displays to the LCD on my laptop. But they are useful relative measurements, I think.
Panasonic TC-P60S30: One to two frames.
What I think was the Samsung PN59D550: Two to three frames.
Sharp LC60LE632U (An LED LCD, for comparison): Three to four frames.
LG 60PZ550 had by far the worst lag: Six to seven frames.
Thanks frank, I'll add them to the input lag thread. Do you recall which plasma models you were able to get into Game Mode? Also, your desktop background appears to be doing some kind of depth of field blur. Is Windows Aero active on your laptop?