Is "philosophy is critique" insightful or profound in some way that I'm not seeing? Is it anything more than such a vague and abstract definition that you can't possibly say it's wrong, even when it looks like people aren't doing any critiquing but are still doing what looks like philosophy (Priest notes that philosophy has its constructive side, too, but it's built on the critical side -- to paraphrase Nietzche, to create, one must also destory)?
Without seeing the article, I'd have to say it sounds fishy to me. 'Critique' is just a fancy way of saying 'thinking critically', and that just comes down to evaluating things using good judgment, so saying that philosophy is critique is like saying that philosophy is thinking really hard about stuff in a good way. There may be something to that, but at best it's a little too vague to be of much help.
Of course, there are more substantive notions of critique (the Marxist notion comes to mind as an example), so it's always possible that he has one of these in mind. That would certainly be interesting. But then it would need a serious defense, since the more substantive the notion of critique, the more doubtful (at first glance) the statement "Critique is what philosophy is."
The most plausible way of making 'philosophy is critique' work, at least that I can think of, is to connect it with something along the lines of Aristotle's notion of aporia (e.g., we come upon things that don't (yet) make sense on what we know thus far about the world -- aporia, or doubts -- and we wonder about them, and philosophy starts with wondering) or Socratic ignorance. That would at least give you something concrete to start out with, and to be profound about philosophy in general you'd need to start out concrete.
i sometimes get very annoyed at the things people in philosophy say about philosophy for this very reason. I do history of philosophy, or I consider myself to be doing what I call history of philosophy, and that's very metaphilosophical in nature. As I've noted before, a great deal of what you do in history of philosophy is handle 'the problem of the philosophical problem', so it's metaphilosophical in that sense. But it's also metaphilosophical in another sense, in that you can't really say anything about philosophy without grounding it in the history of philosophy. The history of philosophy is your data, your connection to the real thing you're supposed to be talking about. That's why Aristotle, for instance, is able to say such such amazingly profound things about philosophy: more than most philosophers he takes the history of philosophy up to his time seriously, and he uses this to immense advantage (perhaps to greater advantage than anyone has since).
But without history of philosophy there is a great temptation to try to answer the question, "What is philosophy?" without any regard for how people have actually done philosophy across time, across cultures, across language barriers. I once knew someone, fairly famous, who told his intro classes that the universal method of philosophy was 'skepticism'. Such a view cannot possibly withstand serious examination; but now there are hundreds of students, over many years, who have been told it. That annoys me to no end. But this sort of thing is very common.
