I do find that Tumblr seems to be more geared for easy picture sharing, but post whatever you want, it's your blog. I post blogs posts sometimes, and I have friends that post their fics too.
The only thing I don't like about Tumblr is how hard it is to start dialogues. It's nice for post and run style blogging, but if you're looking for feedback or conversation, it's a pain!
ps. added you