Well, for a different angle on an age-old topic, let me offer my most humble opinion -- Dylan has a GREAT voice. To me, the ability to croon like Bing Crosby is a minor talent. But the ability to put across a lyric with the kind of subtlety and complexity that Dylan has is much more valuable. One of the things that I've always liked about Dylan is the way he mixes things together, conveying a range of overlapping emotions that doesn't fit neatly into any one category. Listen to the mix of sarcasm, weariness, playfulness and compassion in songs like "Just Like A Woman" or "Visions of Johanna" -- if that isn't a great voice, I don't know what is. Can you imagine anyone else singing those so well?
I'll admit that Dylan's voice had been a hit-or-miss proposition in recent times, as his songwriting has been. But in his prime (1963-66, with a blip on the chart in 1974), he was a master, and his voice was an integral part of the presentation. I would think that the folk/blues crowd would be able to put his voice in context and recognize how good it really is. Am I all alone on this?