Doesn't seem convenient to me.
First of all, what happens with the super-sized quantities. You'll need an extremely large cup.
And secondly, the heat of the fry compartment will heat up the soda underneath.
Do you think McDonalds would ever apply one of these MOS Walkers?

see that's the thing, i've seen those signs up for months (and assume that they've been available) yet i've never seen anyone actually order one. brilliant though it may be, the MOS walker is most likely due to languish in neglect on these shores

Don't be so negative Jan! Yeah, of course you need a larger cup, but here in Japan the word "supersize" has never been uttered inside a fast food joint. Portions are all much smaller than back home. Even a normal large sized cup would be welcome. I don't think heat transfer would be a serious issue. As for McDonald's, I don't know. The real tragedy would be if MOS held back the patent on this new technological marvel and kept its competitors for using it overseas where it would actually be appreciated.

Mehan, yeah I've never seen anyone order one or walk down the street with one. The sad thing is, I don't even like MOS Burger fries (I prefer the giant onion rings), so even I'm not likely to ever use the damn thing.

Heh, there is a mos burger 3 min walk from where i will be :D YES! This is such a neat idea though, wouldn't be surprised if burger king tries somehting simillar stateside...

Anyways, i can't wait till june 7th when i'll be on a plane to tokyo for a stay of 3 weeks... Be nice to be back after so long :P

Keep up the good work Jamie!

Actually, there's a chain restaurant here in South Korea that has these. You can get them with fries, chicken tenders, coconut shrimp, and a few other things I can't recognize. It's awesome on the walk home from work.