I run it in 2006 and will again in the coming 2008. In 2006 there was no ice or snow to speak of, since it is a very coastal maritime climate, despite being so far north. All the pavements are gritted or sanded for ice anyway, so I think it would be possible to always run it in a trail shoe, even if they had a big dump of snow (pavements would be ploughed anyway.)
But since I have Icebugs for training anyway (I live in Norway) I will take them and a pair of trail shoes with me. you could probably take an ordinary pair of shoes and play it by ear - if the conditions required, you could nip into a shoeshop at the last moment and buy a rubber flimsy-thing of stretch-over studs that pensioners etc wear to not fall over. They wouldn't be ideal but they'd do. See you there - I have a blond pony tail 