This is a kind of tired subject as far as writing goes, but I've noticed a LOT of it in fanfic and thought it might be worth a mention. Does anyone else find it irritating when a fic does a whole lot of 'telling' instead of 'showing'? Not that there's anything at all wrong with the occasional 'she was tired', but when I read entire fics made up of sentences like 'Booth thought Brennan was irritating, she was so uptight and annoying ' I start to lose interest. Maybe it's a personal preference thing, but it just feels... stylistically lacking, I guess. Don't say he finds her irritating, show us - have him snap or roll his eyes or something. And again, don't say she's uptight and annoying, show us through her actions, speech, etc. (which I don't think she is, btw, before people start throwing things :P).
I also did some googling and found a page here with a (very) short article on showing vs. telling, and below it is a discussion that has arguments for both sides, which I thought was interesting.