No one can debate there is a skill involved in DJ-ing, but does that make a DJ an artist?
I believe that there is a form of art as the mixes produced are a form of art, layering, cutting, filtering, adding effects, ... There is more to DJ-ing than the act of playing songs in a sequence and it's not only about song choices.
There is an artistic process at work ! A DJ picks music that already exists and packages it in a way that makes it appealing to an audience, makes a link to them, let them experience and share this link.