I'm in the one big ass monitor camp too, I've got two 20s right now and one is almost wasted (it's the Outlook, chat client, and music playing holder). I've tried actually utilizing both but my field of vision feels off the whole time because I dont like having the break between the two centered, too much context switching. But to each their own.

I've really gotten into adjustable monitor arms; I have 3 x 24" and a laptop stand, all on dual ergotron arms. Being able to reassign monitors on multiple systems (mba, mbp, desktop linux, system-under-test) is really nice.

I'd probably add a core 30" if I didn't already have more 24" than I needed at the time. 30" + 24" portrait (2?) is probably the sweet spot for a single desktop machine + laptop.

Count me in too. I'm just not a fan of tennis. One 2560x1600 monitor feels much more fluid than tracking my head across two monitors that amount to a 16:5 screen with 3" of deadspace (bezels) running down the middle.