You know, this thread has turned into "I believe FF13 will sell more because it's a game I will enjoy more!" There's no logic behind those responses, really. o_0

Exactly!

This is completely true, it's not even really an argument although maybe you could say that MH is getting bigger than FF looking at the sales on the PSP but MH has a short history, FF and DQ have a long history and DQ has been more popular. 

People that are saying FF are ignoring all logic.  Historically DQ is bigger, in addition DS is much bigger than PS3, it's really not even close. 

DQIX will win definitely.

The only way for FFXIII to win in the first week is if DQIX gets a really low shipment, which probably won't happen. In total sales there is no contest. FF will really have to struggle to reach 2.5 million on PS3. The size of the install base does matter, just look at RE4 on the gamecube. Also there has been a downward trend in Final Fantasys sales lately; FFXII didn't sell very well, though that may be because the game  was a bit too different.

I think DQ9 could possibly beat booth DQVII's record and DQVIII's worldwide record. Portabiblity is a huge plus and the DS is pretty much the most popular gaming device ever so if things go really well it could go past 5 million in japan. I also think westerners will be a bit more forgiving of the series slightly retroish elements on the DS so it could do relativly well worldwide.

Look at the FFXIII BD bundle demo version sales, I really doubt if FFXIII can reach 1 million sales in Japan but it would be the best selling PS3 game. For DQIX, it is hard to say cause this is the first handheld version and I would guess 2 - 2.5 million sales in Japan.

2.5 million for Dragon Quest 9 seems like a really low estimate, it would be the lowest since Dragon Quest 2. Obviously the effect of going handheld can go either way but I think it'll most likely do at least as well as on consoles. The DS remakes has sold just as well as the remakes on consoles and there are also a number of quite successful spinoffs on the DS so it's obvious that a large part of the fanbase owns a DS. Being portable can also be very beneficial, especially in japan, and it could very well see a NSMB-like effect.

I think 3 million is the worst case scenario, 4.5 million in a really really good scenario, and in a best case scenario it will keep selling forever like Mario Kart and NSMB

DQIX will sell 2 million first week the very least.

Ok then... we just compare sells when they come out. Let's see who was right at then end ;)

DQIX... I mean no contest you have an install base of 20 million in Japan and DQ is one of their favorite RPGs.

Personally I wonder how DQX will do in Japan, it could be the kick that Wii needs to go back to normal sales.