That's a question that I hear often. Probably right after "Will I get accepted?" comes "Is my writing good enough to get me in the program? Is it good enough for me to be in the program?" and so on. So it occurred to me that current MFA candidates might want to link to webpages where MFA work is displayed. I'm not saying this is a perfect way to "gauge" one's writing (far from it), but it'll certainly give applicants some idea (or at least, it'll allow them to satisfy the insane curiosity all of us feel before applying :)).
However, I can't emphasize enough that these references shouldn't be used to respond to the above questions in a conclusive way. Why? At the very least because of these two reasons: for one thing, your work may have nothing to do with the work posted online by current MFA candidates, and yet the admissions committee may very well like your writing; then you're in and you have nothing to worry about; for another, I suspect (though this is sheer speculation) that those of us who post our stuff online don't turn in our very best work -- we "save" that to send to lit mags.
Still, with these qualifications in mind, it might be interesting to see what kind of work online MFA journals or MFA-related sites are posting out there. I'll get started by linking to Crate, the online MFA journal at the University of Massachusetts-Amherst. (This is my second year here at UMass). Also, here's a blog where Rachel Glaser, one of my fellow UMass MFAers and an excellent writer, posts her work.
Let me warmly encourage other MFA candidates to post links to their program's work in the comments section!