well first the stealth genre is less important than the FPS one what so ever... second yeah the install base count.... 3rd wikipedia numbers are less reliable because it's not relying on a statistical basis which is more accurate and gets always more accurate as data arrive....wiki it's just an approximated number put there by some dude...... even if some numbers on wiki MIGHT be closer to reality than on VGC... over all you'll find more accurate numbers here than on wiki and that's a mathematical fact...
p.s. nothing to do with this post... but stop comparing CoD4 to Halo 3 it's stupid.... it's like if I was comparing mass effect to final fantasy or mario kart to GT5.... it's not because it's 2 FPS that it's comparable... I don't like CoD or for that matter any realistic military FPS game... yeah graphicaly it looks better... the rest it's a total question of taste... and no way you can compare it.. the gameplay is not the same, the setting is not the same, the physic engine is not the same AI is not the same, the story etc... oh one bad thing about CoD 4 the background look to have been drawn by a 3 years old.... without saying that you can compare architecture in the real world with CoD and not with Halo... how can you say that complex is not well done, it's a pure creative choice that can't be compared to real world settings...
and BTW I think it's also that which makes Crysis awesome it's kind of a game half way through both of those FPS style... mixing the best of both...
by then on console I don't see any futuristic FPS matching halo 3 anytime soon... I mean the style of gameplay etc.... maybe a new quake
