Is "party ranking" a genuine ranking system? From some discussion here, I surprisingly found (by googling) that there are some ranking for top universities for partying. From USA Today and Time to Playboy, they list top universities for party and nightlife.

I understand that there are not quantitative factors to make such rankings, but are they genuine rankings or just practical jokes?

It is a fact that some students go to university to have fun, and care about such activities in their future university. Thus, such rankings can attract some students, which is still good for a university.

My question is: Do university take such ranking seriously? I mean, are top party universities proud of this feature and advertise to attract interested students?

Universities are proud of their athletic teams, and use their achievements for advertisement, but what about partying? (I ask because this is the first time I heard about naming top universities for party).

NOTE: I do NOT exclusively mean partying. I general mean any ranking considering extra-curricula activities, any ranking based on factors other than education and research.
Universities aren't pleased about ranking highly in such competitions they didn't ask to participate in. That is at least their official position. As it might help with recruiting, some people dealing with attracting students might quietly approve; but in the same way it attracts certain people, others will be repelled. The university in the above link has a great academic reputation as well, and would probably do just fine if it didn't have this other one. 

Other than "being known as a 'party school' ", or appearing in 'rankings' such as Playboy's, I don't think there is any publication that evaluates extra-curricular activities. However, schools greatly value to be seen as a good place that people like to spend their formative years at. When I was accepted for graduate school at NYU, I got hardly any information on their academic side, but a beautiful hardcover picture book on Greenwich Village. Places that don't have natural advantages still care about presenting the school and its surroundings as desirable living locations. The tongue-in-cheek "Where the hell is Grinnell?" slogan comes to mind (it's in the middle of nowhere, but both the town and school are rather beautiful). In addition to mere location, social activities on campus are certainly highlighted in information about the school, and when visiting on site.