I think a lot depends on the personality of the performer. If they can keep my (and the rest of the audience) interest, I don't mind whether they are telling jokes, giving a bit of background to a song or whatever.

I do get frustraded with the ones who go through lengthy tuning sessions in between each song though and fail to see why it is necessary - OK in instrument might need to settle down a little but should not need the amount of fiddling about with that I have seen some do. Also, I would have thought that some performers who know they are going to use say DADGAD and standard tuning on a guitar could either oraganise their sets a little better or use 2 guitars.

Jon