I preordered Xenoblade Chronicles. I played the European version and thought it was pretty good. I'm not usually into such Japanese style RPGs, but there's just something about a story taking place on top and inside two giant mechs frozen in battle. I think it's great that Nintendo decided to bring it over, even though the market for such a game is limited and very niche.
I don't think Project Rainfall had anything to do with it. I think Nintendo looked at their calendar and realized they had nothing. So they just grabbed Xenoblade because it had a British localization and they figured that would be close enough and free is better than paying for a localization of anything else.
As for other Project Rainfall games, don't hold your breath. Nintendo doesn't sit around sorting through fan letters to decide what's best for their company. If they did that all we'd have are sequels to Ocarina of Time and Super Mario 3.
However, if Nintendo takes another look at their calendar and decides it's needs something, anything, to get them by before the Wii U hit's it's stride, we may see Last Story and Pandora Tower come over like Xenoblade did. But not because of Project Rainfall.