Friendfeed feeds friends on Twitter - but why?

Friendfeed now offers an ability to post updates to Twitter, according to the Friendfeed blog. I saw this from Louis Gray's post, (via Twitter) which notes that:

The result essentially turns the lifestreaming functionality on its head. Rather than just have Twitter play a major role in inputting entries in user's feeds, FriendFeed now gives Twitter the chance to do more than operate as a microblogging tool, taking your personal FriendFeed, and mirroring it back Twitter's direction.

In other words please come and live your lifestream on Friendfeed, and we'll still tell all your Twitter friends what you are up to

For chatterboxes on Friendfeed this may seem like the opportunity of a lifetime to aggregate the rest of their lives and dump it on Twitter, but of course one of the strengths of Twitter is people can turn you off - and that has a strong moderation function. (In fact my main use of Friendfeed is to send all the noisy Twitter "power users" into it rather than following them, and get a once-a-day digest that I can scan in minutes - and to publish Broadstuff for people who would rather read it there.)

The question of course, if you are already on Twitter (which is the case for the far larger number of microblog users), is why add another intermediary to your personal workflow at all? To my mind Friendfeed - at the moment, anyway - is neither fish nor fowl. Its not closely linked enough to be a useful Twitter app, but it clearly doesn't really have a standalone role given that Twitter does most of what it can well enough, and has a far larger user base.