Here’s a handy update for you. Posterous now has permissions controls that will make it easier to decide what can post to where. Given Posterous’ latest move of integrating all of your sites, it’s easy to see why this simplicity is golden:

So to break it down, wherever you’re wanting to post, you’ll be able to change settings to make sure that things go only where you want them. It’s really no wonder that Posterous is growing at such an amazing rate.