If I went back to one screen, it would have to be a larger screen with great resolution. I tried going to a 32" HD TV monitor and did not like it because the fonts and such were very large and the desktop was too small. I would like to have the dual monitor desktop grow in perspective on the larger screen to give me the same desktop size as a dual monitor setup, but with a larger singl screen. I don't think the tech is up for that yet at a reasonable price. :)
My friend uses a single 32" HD screen for his system and I find it cumbersome because I am not used to the shortened desktop. I find myself always wanting to stretch out the GUI, but can't.
I use dual 22" screens side by side and I am ok with it.