The real deal is that Pinterest is screwed either way. These terms sound scary but so long as they are enforced sanely there should be no problem. What do you expect them to do? Assume liability for users posting content they should not be posting? They might as well not exist. A lot of startups these days may as well not even try to get traction as long as bloggers keep getting their panties in a twist over every TOS they see.
Pinterest provides a service for free that people seem to love. So long as no one is paying them and they haven't gone public they're damn smart to have these terms. If I ran Pinterest I wouldn't want to assume liability for some asshole who leaks a top secret photo on my site that I let him use for free and as long as I'm giving that service for free I'm going to make some cash out of my users. This is nowhere near evil. It's business. If someone doesn't like it they don't have to use it.
Question: How do you get over writer's block? Answer: Start reading some terms of service or privacy policy docs from any popular online startup and manufacture some outrage over it. Truth is, if you read any TOS or privacy policy you're going to find something you can turn into a big deal most of the time. I've had it with the TOS/privacy policy outrage blogs.