Seems reasonable, with the exception of points 4 and 5.
I suspect lost sales to 360 will not be worth the return on Sony stake in SE.
At this point I wouldn't hazard PS3 will look better. I think the only point of differentiation in the PS3 favour that we can be sure of is 1 disc vs multiple. As for graphics, gameplay, etc. there's no way to tell yet.
In many ways I think this was a clever play by SE. Keeping it exclusive in Japan shows solidarity with Sony and should confirm massive PS3 boost and FFXIII sales, while muliplatform outside Japan is sure to net them more sales than exclusive to PS3 as they will surely gain sales in US (and to a lesser extent Others) that they would not have got at all if the game was PS3 only.
Try to be reasonable... its easier than you think...
