Conflicts of Interest

My favorite technology writer is David Pogue of the New York Times. He brings a personality and depth of knowledge to his work that surpasses anything else I read. (Plus, my kids know every word to his "I got an iPhone" ditty.)
But he's becoming a brand all his own, which leads people to raise questions about conflicts of interest. Those questions hit the page of the public editor today.
What do you think? In an age when information is so fragmented and people have to innovate and expand to build revenue streams, how do we avoid conflicts of interest? Can we? Is the appearance of a conflict as bad as a conflict itself? What if Pogue weren't writing about tech and instead, say, politics? Would it be OK for him to put out books on different people?