You bet she's serious. I'm a defense-side labor attorney. That means Ithat one of the things I do is defend companies when people sue them for discrimination, harassment, etc. It can be a pretty dirty job.
Myspace is public and fair game. It's one of the first places I check when I receive a Complaint that involves a plaintiff under 30 or so. So be careful what you put up there, 'cause if I get you in a deposition, I suddenly know a lot more about you than you think I do (particularly if you have a blog!)...and that will not help you one bit.
A good HR assistant will check myspace too. So, look out. The good news is that all we do is enter your first and last name into the search feature--we don't expend more effort than that. So, we're easy to thwart. Change the spelling of your first or last name or use a nickname as a first name. And be careful when you create your publicly accessible myspace name. For example, if your name is "Jane Smith," don't have your myspace profile be www.myspace.com/jsmith or www.myspace.com/smithj or some easy variation thereof.
Of course, if you don't put raunchy or subversive stuff up there, you probably don't have to worry...or I guess you don't have to worry about anything but a boring profile. 
Happy surfing!
