I’d like to think that I’m pretty intelligent, but I read Zizek in large part because he makes me feel idiotic by comparison.
Zizek has many gifts, one of which is turning over every rock and log along well-worn philosophical paths and finding something new. He looks at topics from as-yet-unconceived angles, and often, his books are thick with intellectual revelation on what feels like every other page (as is true in the Parallax View, for example). And of course he’ll mix in the obscure pop-culture reference or obscene joke to keep things fresh.
From a political standpoint, Zizek is a Communist, and an unapologetic one at that. This is desirable in a healthy society in that radical viewpoints (at least on the Far Left) move a society forward and prevent ideological stagnation.
Almost as important is his status as an “academic rockstar.” People need to see an edgy academic with a personality. Agree with him or not, his visibility is good for philosophy and academia.
He makes me what to be an academic, and a philosopher.
I highly recommend Zizek!, a documentary about the philosopher. It should be available on Youtube, in playlist form.