I found a list of the most expensive colleges (http://www.campusgrotto.com/most-expensive-colleges-for-2008...). I don't claim that this is an authoritative source but I've seen very similar lists elsewhere). There are three colleges in the US that break 50k per year for tuition, room, and board. There are quite a few more between 48k and 50k, though, and so with a standard tuition hike of a few percent they'll be over 50k next year.

My own institution is proud to be doing its own "lowest tuition hike in 41 years", at 3.8 percent. Thankfully I'm a PhD student and so I don't actually pay my own tuition.