Questions for law review authors/editors re online journals and journal supplements

I've noted with interest the proliferation of online law journals that publish short academic pieces. The development raises several questions:

1. Is there a centralized forum (comparable to BE Press' Expresso) for submitting to online journal supplements?
2. If not, has anybody assembled a list of online law review supplements with directions as to how to make submissions?
3. Is there a pecking order?
4. Over the years, I have a number of long blog posts that easily could be expanded and footnoted to make 3,000-5,000 word essays. Would the fact that the article began life as a blog post be deemed preclusive of publication?
5. Is there any good reason to turn such a blog post into a more fully fleshed put but still quite short commentary? Any good reason not to do so?

I'll publish helpful answers.

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