I don't agree .. not many sites use multiple columns at the moment, and they can still look reasonably good (current). If not having multiple columns is a deal

I don't agree .. not many sites use multiple columns at the moment, and they can still look reasonably good (current). If not having multiple columns is a deal-breaker for a user, they'll switch browsers (which might not be such a bad thing). My point is, the fact that some browsers haven't implemented some features yet shouldn't be problem. A website usually doesn't need to look exactly the same on every browser - and following a system of progressive enhancement allows a developer to use newer features more openly.