I had never actually heard of Jackson or known of any of his work before Lord of the Rings, but I must admit (and this is from a guy who often criticises the films and Jackson's take on them) that he and his crew did a good job on capturing the right feeling of ME.
I guess there are some director's that get pigeon-holed into their unique style of directing. Tim Burton, Terry Gilliam, and Jean-Pierre Jeunet are pretty good examples of this. When you see a film buy one of these guys and not know it is directed by them, but yet know their other stuff, you could almost look at it and guess that they were the director. This would be harder to do with something directed by Spielberg, who still has his own unique style but it is more mainstream and not as immediately recongnizable. Del Toro strikes me as more of a Tim Burton, Terry Gilliam, Jean-Pierre Jeunet sort of director. I have only seem a couple of his films, but they have a kind of unique Del Toro-esque thing going on in them. I would hate to see somebody do to The Hobbit what Jean Pierre did to Alien 4, he added his uniqie style to it, and I like his style, but it just worked better for films like "Delicatessen" and "La Cite des Enfants Perdus" than it did for Alien. I like Del Toro's style, but I don't want The Hobbit to come out looking like "El Espinazo del Diablo", "El Laberinto del Fauno", or "Hellboy".