AdmiralViscen stop putting words into my mouth please. Does a game have to be best seller to boost PS3 sales to 20k? If you think so, then well, you are pretty mad. Ninja Gaiden was an XBox game, so in no way could it be successful in Japan (it did sell over million world wide though). It's an amazing action game, one of the best, with amazing graphics as well and competitive play thanks to online rankings, I have no doubt that it will sell more than 100k in Japan alone, and it's surely enough to bump PS3 sales.
Segata, like I already said above, not many Japanese gamers had a chance to play Ninja Gaiden. Not only that, but to me, a big NG fan, changes in NGS are huge. In fact they are huge either way, 3 new chapters will add at least 3 hours of gameplay, there are new boss fights, some of them really amazing (Ryu vs Doku, Rachel vs Doku), new enemies, fighting on water, and new weapons. It's Ninja Gaiden Black 1.7 IMO.