The 'Blue Dragon Sales Boom' was only relative to previous sales on the 360. Though I think it may have fared better in Japan initially if it wasn't released right next to a hotly anticipated Gundam game.

Last week, Famitsu listed the top 50 360 games in Japan.

Blue Dragon is #1 at...203,740. It's been out for an entire year, and it's just over 200,000. (Though I think that's like a 50% attach rate, so it's not abysmal...considering.)

I don't think Mistwalker has to worry too much about their games flopping on 360. Microsoft is paying them good money. It's really Microsoft who would have problems, since they're not seeing any good return on the money.

As has been mentioned, they are a 3rd party so they aren't owned by Microsoft. Microsoft only owns the rights to the Blue Dragon game and Lost Odyssey, so you likely won't be seeing those particular games on a competing console.

As for opinions on Mistwalker themselves, can't say I really have one. I haven't been interested enough in any of their games really, particularly after having played a good bit of Blue Dragon (though I was excited when I first played it). The most interesting thing coming from them is Cry On, which I coincidentally know next to nothing about. And even the bit I do know (game apparently makes you cry) isn't particularly appealing, but at least ambitious.

I do hope they become successful. Blue Dragon DS is their best bet for now, since everything else doesn't seem to have done too spectacularly.