Capn Bloggs
The 330 can operate without one but with a extra burn to account for - see the 330 that sawed off a Dash 8's tail at YVR recently.
CO are pushing the 757 as a east coast US to British Isles/Western Europe option, thus the wingleting. Icelandair are also doing it (since Iceland to pretty much anywhere is medium haul at least) and apparently AA are looking at it too, as they also have 757s they can replace on SH on with 738s.