I think this is an inherently difficult question to answer. I guess first you have to define art, which I would do by describing it as an indirect way of conveying meaning. By that definition, if an artist has a point, then if he is able to convey meaning to someone else, then it’s successful (pretty much what @YARNLADY just said). You can’t really say if it’s “good”, that’s just too subjective…there are a lot of people who don’t think Picasso was “good”, but he was successful at conveying what he wanted to convey in an indirect way…one in his case which hadn’t been done before. You could say the same about Dali, a lot wouldn’t get it, but he did get his point across. Now those two were trailblazers, but it doesn’t mean that once they did it, no other artists were successful in that same “genre” of art. But conversely, just being the first to try something only makes you a trailblazer if it has meaning to enough people and is inspirational enough to make others follow your lead. So, I would say, perhaps no one has tried exactly what’s going on in London right now, but people have been used in art pieces before, so it’s hard to say this person blazed a trail. But does he have a point to make, or is he just fashioning something interesting. I guess if time shows that people read something into it, then it’s probably successful, if it’s just like that guy in New York who draped Central Park with orange fabric, then maybe not. Bottom line, yes there is a lot of uninspired work being heralded as art, and there is probably a significant amount of real art that goes under the radar.
And one other thing to consider is the medium, or rather media these days. Art is always limited to the media available, so in the past we had painters and scultpors and musicians…but now we have film artists, web artists and a whole host of multimedia artists. And great art basically is something that outlives its creator…we may not know what today’s truly inspiring art is until after the artists are dead…that’s how it has always worked. Maybe the best art we have now is people who make movies…who’s to say that Da Vinci wouldn’t have been a Scorcese or a Tarantino if he’d had the medium of film to work with? Maybe the great art exists within animation these days, maybe the creators of animated TV series or graphic novels are today’s most talented “artists”. Certainly music is a form of art, and whereas some music is great, others…not so much. In fact, popularity, which the aforementioned piece seems to have, is not a harbinger of quality, and music illustrates this better than anything. Clearly the new Hannah Montana record is going to outsell the new Elvis Costello record, but which one is actually art, and which is commerce?