I'm an 21 year old RA at Northeastern. We can drink, but not be in the presence of underage residents while we are doing so. Also, RA's, Pro-Staff etc. check facebook profiles, myspace, and webshots to get an idea of what we have to look out for, but the policy here is that we can't police the intraweb. If it was done in the past, not much we can do about it. However, we do take note of the kids that are posting pics of them being sloshed, high, stoned, and whatever else the case may be and pay them a little more extra attention.
Since we're also a Co-Op school, a big concern here is that Co-Op employers and faculty can look at these sites and figure out if you're the type of person they want to hire.
Kids don't have any clue how many people look at the information that they put out there themselves. Then they bitch that it's an invasion of privacy, ignoring the simple fact that they posted themselves for all to see, they should suffer the consequences.