Performance might matter at huge resolutions with lots of clients; it's sort of up in the air. I'm probably going to go SLI whenever I upgrade again, not out of need, but because I'm only using 3 monitors, I do occasionally game, and why not.

Regarding productivity, I've adjusted. I almost don't miss the extra row from a productivity standpoint. Almost.

And a tightly clustered group of VideoFX is the best for at a glance stuff; e.g. follow/positioning/whatever. I'd probably do that even if I had the real estate to run everyone full-screen. With VideoFX you can do a lot of interesting things to get important information in front of you. With diablo 3 I confine myself to two of the three, but if I did another MMO i'd probably use the center monitor for the 'main' with the right hand side divided into video fx's for the followers. I'd maybe keep a slice of DXnothing to the 'near' edges of the two side monitors to stick VideoFX viewers from the slaves that are useful, such as slightly-scaled down mini-maps, health bars, whatever.

For me, the 3x2 was really a holdover from my day's of hardware boxing. If I had a setup dedicated to strictly productivity and boxing, I might stick with it [even if I normally focused on the bottom 2-3]. Part of the 'ignoring the top row' is due to my eye level being aimed at the bottom center; not the center of the 3x2; so it was a bit of effort to 'look up.' You could mitigate that aspect by raising your chair or lowering your monitors, to be fair.