Derren Brown is one of the few stage magicians who actually knows what his job is. Unlike most of his contemporaries, he understands that once you've achieved a certain level of technical ability, professional success hinges on presentation, not further refinement of that technical ability to absurd levels that only other professional magicians will even notice. Whereas most magicians like to show off ever more complicated, intricate methods (in other words, tricks) to one another, Brown has learnt to stick with comparatively straightforward tricks, instead concentrating his effort on dressing up his performances as true spectacles of wonder. He doesn't give the audience the puzzle of how he did something; he gives them the possibility that he did something impossible.
With most magicians, you know that magic isn't real, therefore they must be using tricks. Brown is smarter than that, and realises that his audience is smarter too. He gives people several layers of patter (in other words, bullshit) to choose from when deciding what to believe. He'll dress up tricks in such a way that people who believe in mysticism will believe he's psychic despite his protests to the contrary, while more knowledgeable people who are slightly less gullible may instead believe he plants subliminal messages and reads body language to feign this ability. Indeed, he does plant subliminal messages and read body language occasionally, just not exclusively. As smarter audience members believe they see him using these techniques, however, only other magicians even think to look for sleight of hand at work.
These days, any magician can hide from the audience exactly which trick he's using, but only Brown can convince the audience that he's not even performing magic tricks in the first place. I think it speaks volumes about him that people often describe him as a mentalist who used to be a magician. He combines the showmanship of the psychic medium with the proven skills of the magician. This enables him to look more interesting than other magicians and more accurate than any psychics. I wholeheartedly recommend his stage shows, TV shows and especially his books to anyone.