Shockingly, I have yet to see a thread about SO4 sales so felt the need to change that. :O
With that said, what do you think will be first week and lifetime sales for SO4 in Japan? It comes from an established franchise so it should do well, I will say 150k first week and 300k lifetime sales for the game. It remains to be seen if Yakuza 3 which releases a week later has any affect on SO4 sales, people might just save their money for the latter game.
In terms of hardware sales I expect the 360 to outsell the PS3 that week for 2 reasons. One reason is that SO4 releases with bundles and secondly Yakuza 3 releases the week after so it is likely people might wait for the Yakuza 3 bundle or what not. So 20k units SO4 release week.