Still a bit of a beginner myself, but my understanding is that UV filters are there to protect the lenses from damage by UV radiation, prevent hazing in your lenses, and protect your eye from UV radiation. It does not have anything to do with picture quality and is more of a protection/safety thing.
I've never heard that one before. I'd guess that if there was enough UV radiation to harm a lens, even over time, then the photographer would have suffered serious damage.
http://www.dailyhaha.com/_pics/burnt_to_a_crisp.jpg
As mentioned, I think the most common use of UV filters are physical protection...as in, it keeps crap from getting onto the front element of the lens and might take the brunt of a fall if you drop the lens etc. Of course, there are 'clear' filters that do that, but people seem to use UV filters just as or more often. As for the bennefits to the image quality, cutting UV/sky haze etc....I don't know, maybe. :scratch: