For anyone interested in genre fiction, discussions about fiction, and feminist discussions about fiction and fandom, there are some great recent posts from authors calling out reviewers on using the term Mary Sue.
Starting with this terrific breakdown from Zoe Marriott:
You Can Stuff Your Mary-Sue Where the Sun Don't Shine Additional comments by Holly Black:
Ladies Ladies Ladies And the always-excellent Seanan McGuire:
I know a little girl and her name is Mary Mac: The Misuse of Mary Sue. A related post that briefly mentions the Mary Sue issue from Sarah Rees Brennan:
Ladies, Don't Let Anyone Tell You You're Not Awesome At this point I have to add Brennan to my next trip to the BPL: I have no idea whether I will like her books but this is the second completely awesome blog post of hers I've read (I bookmarked the other one back when I was linked to it, must get info off other computer) and I think that deserves giving at least the first novel a chance.
Sorry this is kind of link-spam-y, but I never get tired of talking about writing and critiquing female characters. I've only rarely used Mary Sue/Gary Stu, but after this I think I will retire the words from my vocabulary entirely.