I've never seen the Dog Whisperer's show, but I've read and read tons about this man, Cesar Millan. He is a miracle worker, seriously. It's amazing some of the stories I've read. He's taken dogs (anything from teeny tiny Chiuahuas, to huge pit bulls and great danes) that everyone else said to put down because they were so bad it was hopeless, and turned them into perfectly balanced, well behaved dogs. It isn't that he can read thier minds per say, or commuicate with them telepathicly, or any of that mystic hocus pocus. He just has a firm grasp on the way they think, and what they really need to be balanced. And his methods are very simple, nothing complicated.
I'd highly reccomend checking out all the tips on his site, and reading his books (I'm reading one right now!

), even if you don't have any canine-related problems. I learned more from The Dog Whisperer than I have from any other book or website I've ever read.
As for 'Pet Psychics', that is a matter of opinion. MY opinion is that the idea is quite overrated. Reading an animals mind isn't as hard as it sounds, when you consider the fact that they use body language extensively to communicate how they are feeling and what they are thinking at the time.