Sony probably wouldn't do this, but I could see both MS and Nintendo jumping on board, although not at a high percentage. It's doubtful another Shenmue game would be as expensive as the others are notorious for, but the main problem would of course be reviving the series and name. That would be the most risky part.
The reason I mention MS and Nintendo, is because they have been doing this all generation. MS is of course notorious for forking out money for exclusivity and of course helping to fund and develop projects. Nintendo has also been doing similar things, although not to the same monetary extent, but striking up deals and partnerships with 3rd parties. The most notable about that, of course, has been Sega themselves for the Mario and Sonic games which have been commercial hits.
But for the most part, I don't think the hype or potential for a big commercial success is there for another Shenmue game and anyone who picks it up will probably not hit the sales potential they are looking for. But we'll see what happens.
