I'm a big fan of the novella format but also serial novels (Ender, GRRM, etc) so think this is really interesting.
plympton.com are doing serialized fiction, you can get it on the Kindle, though I have yet to read any.
This has been done in newspapers and magazines since before tvs were accessible to the public. Charles Dickens's 'Great Expectations,' for example was published in serial form in his weekly newsletter.