Taking into account the live users average, it would mean around 200k first week. 

it´s not a hardcore game in the hardcore machine.
For me this game boomb very hard
ok i´m a nintenboy but i hype this game between my xbox friends. But they only talk about gtaiv or gears 2. i think this is the problem only hype games sold well in hd consoles.

Doesn't 100,000 refers to the number of people who uploaded their scores and/or videos?

I think 250.000 - 350.000 WW first. It will be a Millionseller in late 2008.

 What? lol.

And EU sales dont' surprise me. I think the U.S sales will be MUCH higher. My prediction still stands.

I'm going to go with 250K US. and probably 40K in Japan.

So finally it sold 216k. People with low expectations turned to be right. I won't be saying who was off the most ;)

@kamil: Obviously it's me, assuming vgchartz is correct. But you haven't counted Japan yet.

Anyway, this is not the kind of game which I would expect to have massive legs. All in all, a very weird situation. Either this will be a hardcore game with legs, or a massive failure despite being a worthwhile sequel to a famous game.

Well all we really have to go in is the data for Sigma, which the new game blows away. Sigma sold 0.28m in the us with a 37,860 launch. Whereas the 360 version launched at 173,443, which means its vastly ahead. We don't have others data so I have no idea how much it sells here. But It'll most definitely have better legs then Japan. If Sigma can sell 0.37 m on the ps3 will a significantly worse launch (and no others data) then this game should go significantly higher. 1 mill could be in reach, but it all depends on the US's legs and how front loaded it is, so I guess we wait a few weeks.

EDIT furthermore its looking like Ninja Gaiden 2 had a staggered launch in others as I know for certain that Australia hasn't got it yet, so perhaps the low first week can also be attributed to it simply not being on sale in enough areas at once. 

Here is Wikipedia's summary about sales of the previous games:

Consumers purchased 1.5 million copies of Ninja Gaiden and Black to August 2007,^[135] with the bulk of these sales going to North America and Europe. According to the NPD Group, in its first month Ninja Gaiden sold 362,441 copies in the United States, with Sigma selling 63,637.^[136][137] As of April 2008, 470,000 copies of Sigma have been sold in Europe and North America.^[138] These sales figures reflect Tecmo's decision to target the non-Japanese market. Japanese gamers were not particularly excited by the games—according to Itagaki, only 60,000 copies of Ninja Gaiden were sold in Japan in the four months following its release,^[28] and Famitsu gives a figure of 76,095 copies for Sigma in its first six months.^[139] The critical and commercial successes of Ninja Gaiden have led CNET and GameSpot Asia to induct the game into their Halls of Fame.^[140][141]

In light of this, it's not so bad, although I would expect a sequel to be more frontloaded.