Another +1 for Panasonic plasma. I bought my 60st50 a year ago this month and it is amazing, the picture is beautiful.
I did a lot of research before buying and for the price at the time it was the best on the market. I am seeing the same results with the new ST60. To get an LED that would compare in picture quality you would have to spend upward of 4k on a full array LED.
If you want a more real to life picture with deep blacks and no worry about light bleeding go Plasma and go with panny.
Oh and you should join here:
http://www.highdefjunkies.com and read through some threads, the couple of professional calibrators namely d-nice posts panel prep and settings for the high end panny plasmas.
I highly reccomend a Panasonic plasma if light/glare are not an issue. I have yet to see an LED that gave a better picture quality or viewing angle than plasma. Downside is they are still big and heavy, not slim and fancy if that matters. Otherwise I would go with Samsung or LG for a LED.
My plasma is heavy but just as thin a LED...