As much as I hate plasmas right now, they are better in picture quality simply because of their design. Being an active panel, plasmas will never have problems with uniformity with their brightness. A led can be edge lit which is better than a single point but still , multiple pixels will be "lit" using a light source as opposed to plasma that has individual pixels that have their own source and can also be turned "off"  instead of dimmed thus providing deeper blacks which equates to a higher contrast ratio. Advances in local dimming are catching up though. Plasmas are also not limited to motion blur where lcds have to use black frames or other tricks to try and disguise the problem. Many lcds also lose their contrast or color as the viewing angle changes but plasmas don't. I think that there may be cases where an lcd will look as good as plasma soon on a consumer level but I think we will have a little waiting to do before they are better.
 
 Even with all that said, I would never touch a plasma again, especially after taking a peak inside and seeing how the panels and main board connections are done. Almost a useless argument since almost all plasmas are EOL anyway.