Hard to say what Konami in particular is looking for the install base to be; "huge" is about as relative as it gets.
I guess that at this point, a huge install base is one that ranks higher than the install bases of other systems. Right now, the 360 and Wii have "huge" install bases (though only by current next-gen standards). Compared to systems from other generations, or the current handheld market, they're considerably smaller, but only because those install bases have had more time to grow.
"Whenever you find a man who says he doesn't believe in a real Right and Wrong, you will find the same man going back on this a moment later." -C.S. Lewis
"We all make choices... but in the end, our choices... make us." -Andrew Ryan, Bioshock
Prediction: Wii passes 360 in US between July - September 2008. (Wii supply will be the issue to watch, and barring any freak incidents between now and then as well.) - 6/5/08; Wow, came true even earlier. Wii is a monster.
