Alternative publishing

I have been looking into alternative ways of publishing recently.  There was a time when the only alternative to traditional publishing was so-called vanity publishing, and no self-respecting writer would travel that route if he or she wanted to be taken seriously.  Of course, things have changed radically.  Vanity publishing still exists as a way forward for people who want to see their book in hard-copy, and who can't get a publisher any other way.  But why bother with that route, expending your own money, when you can publish in the virtual world now?  Naturally, there are e-books, but they originally tended to come after a book had been published in hard-copy.  And print on demand is a route I have taken to get my older books republished.  All publishing systems piggy-backing on traditional publishing.
Now, though, the world of publishing has broken wide open with online publishing companies and self-publishing.  In the early days this would have merely been seen as a form of vanity publishing.  But no longer.  Manuscripts can be formatted and sold through Amazon now.  The problem remains the quality and quantity of self-published books.  Without sifting for quality and editing, many books available in this way can be dire, and the author of a good book can find his/her work lost in a sea of dross.  In the end, self-publishing presupposes self-marketing, and this is an area that many writers have had to undertake in the sphere of traditional publishing, but few actually relish.  Enter Facebook, Twitter, and author websites.  Oh, and author blogs, of course!