Hi Andrew,
I have no immediate plans to build such a feature but of course you could build your own.
Or you could just use the blog for small posts and then use the tweet this button in the blog to send them to twitter with a link back to the post. To me the only reason I use twitter is because it can drive traffic back to the site so it is a useful marketing tool, though I'm not really into tweeting myself. But doing it that way gives you more freedom from the concern about 140 chars. You can't really edit tweets after you tweet them anyway as far as I know, but you can edit the blog after tweeting.
Best,
Joe