1a) There was a kerfuffle regarding this in the past, so to be clear: it is acceptable to base your SSBB story on copyright characters, as long as all names and enough worldbuilding details are changed. However, if the story makes less sense to someone who has no knowledge of the original series than to someone who is conversant with it, it counts in practice as a violation of the standalone rule (3c). Note that I don't say "less funny", but "makes less sense". *g* Basically, if you are going to do this, make it the kind of AU where regular fanfic-readers would complain your version of the characters/setup had no relevance to canon whatsoever. If in doubt, email the editor.
Secondly, fanfiction typically appropriates settings, plots, and specific scenes from canon. Even direct quotes are all right in fanfic, in the sense that it can't be considered plagiarism, because the source is clear from the context. If you then take that and switch out the names to make it original fiction, though, it's no longer so clear. Thus, there is to be no direct reappropriation of text or plot points from a different work, unless permission is given and it is credited. Again, if in the slightest bit of doubt, let the editor know and we'll figure it out.
1b) Live-people RPS is acceptable as long as all the names are changed to maintain plausible deniability. Historical RPS is acceptable without name changes, at least until the threat of legal action by ouija board becomes a possibility.
2) A contributor may submit only one story to each issue of Bang*Bang.
3a) For publication in Bang*Bang, the lower bound on word count is 100% non-flexible. If you submit a story that's less than 1500 words long, I will send it back and ask you to make it longer.
3b) The upper bound on word count was instituted as a way to prevent people from writing novels, or multi-chapter stories. There's nothing wrong with novels (other than the risk of them being left unfinished), but SSBB was created as a showcase for one-shots and not serials. It's not difficult to tell the difference between a chunk of novel and a short story or novella. If your submission doesn't fit in an LJ entry, I'll ask for edits or bounce it for not being in the acceptable format - especially if you admit that the idea is "unfinished".
As of July 2007, writers have the option of contributing a longer story. The Nebula Awards define a novelette as between 7,500 words and 17,500 words; for convenience, the SSBB limit is two LJ entries, or approximately 22,000 words. The story must still be self-contained and appear in a single issue. The onus is on the writer to split the text where appropriate and make sure both halves fit in an LJ entry. Please note that I am NOT trying to send the message that stories should be as long or plot-filled as possible - quite the contrary! For a publication like SSBB, a mix of lengths and styles is best, and many readers like short stories better. If you end up with a submission that is 12,500 words long, I would prefer you cut it by 1,000 words rather than ask to post it in two entries.
3c) Consecutive short stories featuring the same universe or the same characters are acceptable, as long as they're self-contained. If a new reader cannot understand what's going on, who the characters are or what their relationship is without referring back to a previous part, then the story isn't self-contained. In practice there is some leeway if you have written several standalone stories with the same characters for SSBB and have a reasonable expectation that readers know what's happening. Again, if in doubt, email the editor. Or recap. XD
Cliffhangers are of course verboten; "artistically" unresolved endings are subject to editorial judgment call.
3d) There must be a sex scene. It must be rated R or NC17. I know there's a loophole in the rule as stated but it's legalistic as well as largely facetious. In practice I bounce all submissions that I cannot rate R-for-sexual-content in good conscience (and I'm conservative in that regard; I tend to mentally rate things higher than most).
I don't believe that anyone who would read and write for Bang*Bang cannot tell the difference between PG13 and R/NC17! ^^; If your story as it stands is only PG13, don't send it to me hoping that it's likeable enough to run. Likeability - or readability - has nothing to do with it. Between a 2000-word fluff PWP between yaoi stereotypes and a 10,000-word piece with beautiful prose and a gripping plot where the action fades to black at the bedroom door, the first story will be accepted and the second one bounced. That's because Bang*Bang is designed for the first type of story. That many entries are both excellently conceived and written is a gratifying bonus, but not at the expense of the mission statement.
An even more important consideration is that if I make an exception for someone, at this point it would be unfair to everyone else whose stories I bounced. So there will be no exceptions.
When I say "bounce", I don't mean I reject the story outright. I email back asking the writer to make the sex longer, more detailed and descriptive.** In about half the cases thus far the writer made the changes, and the story was published. However all this takes place 3-4 days after the submission deadline when I've had time to read through and vet the entries, but before the issue goes up, so it's stressful and last-minute for both sides ("write a sex scene in 48 hours!"). It's much more time-efficient to make sure the story is rated R before sending it in. If you really cannot bring yourself to do it... have pity and don't force me to play the bad cop.
8) The tag space is getting crowded, so please pick one pseudonym and stick to it for all your stories and/or artwork insofar as possible. Existing multiple pseuds may be used (grandfathered in).
** Writing these emails always makes me feel like I took a wrong turn in life somewhere. orz