Even though I've entered a contest and won a "Feature" in an online magazine (similar to MagCloud/Magcloud(?) only it's "Issu" or something like that), I still agree that I think an actual print magazine is still more impressive than a web feature, or winning some online contest, usually.
There's always Facebook contests where you can be "cover girl of the month", and by cover they really mean cover photo, on Facebook. Not an actual cover of a magazine.
If I were to ever win something like that, I might make it a milestone on my fan page, but I wouldn't list it as a credit on my MM page.
I've been "model of the month" on a Facebook fan page, and again, I wrote it as a milestone on my fan page, but I won't list it as a credit on MM, because I don't think it really counts that much for anything.
I don't think winning Facebook competitions will ever take over being in an actual magazine, but I can see more "official" online contests and digital magazines "mattering" more in the near future.