The main control surface is wide enough, in fact, that we could comfortably put three fingers on the top of themouse, usingthe middle to control themouse wheel and DPI sensitivity adjustment rocker (a nice touch in and of itself) without ever moving our index and ring finger from the all-important trigger buttons.
The current-gen and previous-gen MMOs were all about usingthe keyboard and mouse, and sure, everyone used things like Ventrilo and other voice chat services, but that only works in a small group.