A little while ago I saw an interesting post on Lifehacker about why hearing a cell phone conversation is so annoying. I'd heard this theory before, and agree with it - at least, in my own anecdotal experience, overhearing a cell phone call is way more distracting than overhearing two people having a conversation.
I'd even add one more element to their list: phone calls are more distracting than a conversation because of the pauses. When two people are having a conversation, since one or the other is constantly talking, it becomes sort of a constant background noise (which is easy for me to block out, say, while reading on a train). But overhearing just one half of a phone call, an irregular sequence of noise-pause-noise-pause, is impossible for me to filter out because each time the person starts talking again is a new distraction.
Anyway, for all these reasons, cell phones in a quiet space like a library are always going to be a problem - even in a not-necessarily-quiet library like mine. Until we can get a good white noise generator* that would drowned it out, perhaps what we really need are dedicated spaces for people to have cell phone conversations.
So, thanks to Stephanie for pointing out the cell phone phone booth:
I'm sure a few of these would help, but if we're talking that kind of money, I'd still prefer a fountain.
*All my requests for a fountain in front of the Reference Desk have so far been denied.