"We just launched this new site for British Airways using Storefront ML (with customisation); www.highlifeshop.com. The site launch has been a huge success, with sales roughly doubling those of the old site for the same period." - Tim O'Neill, Reactive Media. Reactive is an AspDotNetStorefront U.K. DevNet Partner.
Site: http://www.highlifeshop.com
Additional new sites:
http://www.spicylegs.com
http://www.swissclinicalusa.com
http://www.chocata.com
http://www.weddingmountain.com/
http://www.imate.com (very nicely re-done...yes, the storefront is in there also, lots of custom mods of course, and very nicely done flash)
http://www.talkaboutwireless.biz/default.aspx
http://www.skygolfgps.com/default.aspx (their developers have done a nice job of customization and corporate site integration)
http://www.staelduinsebos.nl/
http://www.rastaempire.com/default.aspx
http://www.myultraestore.com
http://www.video-line.com
http://www.insyncspeech.com
http://www.wild-mart.com/default.aspx
http://www.readyshoppingmall.com
Nearly all ML sites (I think every one is running ML actually)