Is it going to be Guitar Hero 3? or Mario & Sonic? or Mario Galaxy? or Metroid? or Manhunt 2?

Name	Console	Publisher	Japan	America	Others	Total
	Wii Sports	Nintendo	2.13	5.10	3.39	10.62
	Wii Play	Nintendo	1.70	2.41	2.13	6.24
	The Legend of Zelda: Twilight Princess	Nintendo	0.56	1.98	1.24	3.78
	Mario Party 8	Nintendo	0.84	1.23	0.41	2.48
	Wario Ware: Smooth Moves	Nintendo	0.48	0.70	0.70	1.88
	Super Paper Mario	Nintendo	0.52	0.78	0.26	1.56
	Rayman Raving Rabbids	Ubisoft	0.02	0.58	0.43	1.03
	Red Steel	Ubisoft	0.04	0.45	0.53	1.02
Totals (8 matches)	6.3	13.2	9.1	28.6

The two most likely choices are Mario Strikers Charged and Resident Evil 4 Wii Edition.

Mario Strikers Charged will be the 9th.

Super mario galaxy

Most likely RE4 as Monty said. Mario Strikers Charged and Metroid Prime 3 have chances, but not that soon. Mario Galaxy will sell 2 millions on its first week.

Possibly Metroid Prime 3 as it will be launching in Europe in under 2 weeks. If that doesnt make it then it will be Super Mario Galaxy.

Resident Evil 4 has a good chance, depends on how big the storm will be for the Galaxy launch in Japan. I predicted it will exceed 1 million in Japan alone already during launchweek. My guess is Resident Evil will run 2 weeks short to beat Galaxy as the 9th. But eventually become number 10.

Galaxy will be number 3 by the end of the year.

Edit: Metroid Strikers will be numer 11. Metroid 12.

 Charged has a shorter distance to go, though. Plus it's selling more weekly, I believe. It's a relatively new release in Japan.

http://vgchartz.com/japweekly.php?date=37458

Mario Sunshine did about 338,000 in its first week in Japan, 111,000 the next. I think it will end up being Mario Strikers, it still has a lot of sales to nab in Japan.

Metroid Prime will pass 1 million before the end of the year, but it shouldn't be considered in this discussion. It's at about 500K, and though it hasn't launched in either Europe or Japan, it doesn't sell well in the latter. Something ike 5% of Echoes' sales were Japanese.

How much userbase had the GC at the time of Sunshine's release?

It had a userbase of 1,500,000 aprox. in Japan at the time, Wii right now has 3,660,000 at the time in Japan.

The GC had a over 200% increase in Japan at Sunshine's release, so the Wii will likely reach 4 millions in Japan at Galaxy's release.