http://www.slate.com/articles/life/the_good_word/2011/05/the_caseplease_hear_me_outagainst_the_em_dash.html What think you?
I use it often when posting in forums, as a stronger parenthetical interjection, but it's not something I use in my writing. I don't have a negative opinion of using it. I just don't use it myself.
I use it to interrupt dialogue, but I don't have much use for it where a comma will do. It's doesn't bother me seeing it used by others. Not many writers overuse it that I've seen.
I'm using em dashes because my protagonist couple tend to complete each other's sentences a lot, but I don't really like them. They look too blinking long. I wish there were something between an en and an em.
I have three sizes, a dash - , an en dash – , and an em dash — . You can also adjust the size using a different font with wider or narrower ems.
I like using the dash. I probably don't use it much in my stories or whatever, but it can be useful sometimes - such as when I write on forums like this one (Easiest way to actually use it was in a dodgy sentence like that one hahaha)