It's a good gateway. I realized that this morning when I finished a user-facing feature that builds on TwitterFeed. Why should I worry about how to connect to Twitter. It's become a chore to keep up with their APIs and various conceptual complexities. Let the TwitterFeed guys do that. I can leverage all their work by simply outputting RSS.
If you want a 140-character limit, then don't use more than 140 characters. If you find it ridiculously confining (try to have a "discussion" about any real subject in 140-char chunks and you realize it's hopeless) then write at the length that works for you. If people don't want to read your ramblings, they won't read them. You learn how to make your ideas persuasive, and gauge the interest of the people you're talking to.
It's remarkable how things always come back to the tried-and-true ideas. Does this sound a lot like Dogma 2000 to you? It does to me.
Something else that's really cool about TwitterFeed. I store my stuff where I want to and then tell them where I put it. This is so much more rational that the other approach, where I give my stuff to a website and they decide how I can access it. And of course they can change the rules anytime. See how much better the RSS approach works.
PS: This was inspired by a post on Joe Moon's blog.