I've always tended to prefer the tall skinny route but that is more due to the uses that I'd been using my truck for. This is what I've found.
In deep mud, or really gummy mud they claw right down to the good stuff and push the slop to either side. Even traveling really really slow, like I do when I wheel, the lugs seem to get good purchase. On snow they've been great too. On highway encouters with the white stuff, and we get alot where I live, the skinnies cut right through the crud without any pulling from the wheel caused from dragging into choppy tracked up loose snow on the road. In wheeling situations I've had great luck right up to the depth at which I start having clearance problems, then I think flotation would be better in order to pack down and ride more on top of the snow. My 9.50's didn't give me too much of a footprint for flotation. Sand, was a miserable thing, the truck really had to work, and if the sand was soft, then the risk of getting buried was always there. On the highway in dry conditions, the skinnier tires also give a bit more sidewall flex then comparative wider ones. Not that big of a deal if you don't mind viewing the world on a slant through you windshield a bit.
With that said, overall I was happy with my skinnier tires, but I just moved up to 12.50's, which I'm hoping in the long run, will work better with a little better handling and some flotation.