Font statistics


I feel like this must have popped up on this forum somewhere but can't seem to find anything. I'm interested in statistics on font use on the internet/computer. Things like how many fonts the average user has on their machine, how many different ones are used on websites (now that this is possible) and so on. Can anyone point me to reasonably reputable source/article? (I'm actually trying to create my own font - - but I'm also interested in the broader issue of typography on the web.)

Thank you very much,