The PS3 userbase will be a lot bigger then 10mil in 09...

No game ever has more than 30% attach ratio, except maybe Halo, so it's ridiculous to say that FFXIII will get a 50% attach ratio. 5 million FFXII's on a 100 million userbase does not translate into 5 million FFXIII's on a 10 million userbase. Especially when FF love seems to be waning.

PS3 should easily be over 10million by March 2008.

PS3 4.4mill
Resistance -  1.63

 ohh looki 36% attach rate.

360 10.82
Gears 4.53 

ohh noes 41.8% attach rate.

 FF7 hit on around a 10 mill user base, its ridiculous that it sold 9.7 million.

I think we will keep finding out more at TGS this year.

Are you sure about that?

Realistically speaking, the PS3 will probably have sold somewhere between 5 Million and 5.5 Million by its first year aniversary (middle of November 2007), even if you assume amazing sales over the holiday season the PS3 will not break 8 Million consoles sold at the end of 2007; for your prediction to be true the PS3 would have to average at least 666,666 units per month in January through March 2008 to break 10 Million ...

Personally, I think a more realistic estimate would be 8.5 Million units sold by the end of March 2008

 You should amend that to non-bundled games. Yet so far, Wii sports in Japan has a pretty high attach ratio.

Yeah, so there's a few games...but I highly doubt this next FF will break 5 million, until much later in the PS3's life perhaps.

Attach rates only really work after the console's life is effectively over.

Otherwise, the day after the PS3 launch, you could scream how RFOM had an 85% attach rate. Now it's at 36%. By the end of life, it will almost assuredly be at 10% or less. Even Gears, which has sold in much greater numbers than RFOM, will probably end up just over or under 10% attached, maybe close to 15% if it's lucky.

Edit: Ah, I see you were talking about FF selling 5m. Forget this post.

Even if it's say 20 million, how many copies of FFXIII do you think will be sold? It would have to have a 25% attach rate to even make it to 5 million and that would be even worse than FFIX. As far as I know, Final Fantasy VII had the highest attach rate ever for an RPG with 9.5%.

 Do you really think they'll release it as an exclusive on a system where it'll have to have an unprecedented attach rate in order to have sales that are merely disappointing. If they allow a Final Fantasy game to sell below par when they could have avoided it, Square-Enix's executives will have to face a lot of angry shareholders.