There is a fantastic post today over on Roni Loren's blog about using photographs on your blog. In summation - yes, you can be sued for using a picture you didn't take yourself on your blog. It doesn't matter if you link back and name the photog, it doesn't matter if you acknowledge it's not yours, it doesn't matter if you don't make money off of it, it doesn't matter if it was innocent and you didn't know you were wrong.
As a librarian, I'm very aware of copyright issues. As a writer, I'm very aware of how they protect me. As a blogger, I'd love to be able to pop up whatever pretty picture my Google search presents me with to spice up the latest post.
But I can't - and more to the point - I shouldn't.
One reason I waited so long to create a Pinterest account was because I'm pretty sure the only way to be totally free and clear of Legal-Land is to only use your own pics and not re-pin. So that's what I do over there. Sure, it might be the paranoid way of going about it, but I'm a paranoid gal. For more about the legal ramifications of using Pinterest, read this.
I'm fairly certain that the only pics I have on my blog are ones I took myself, or that I had permission to use. Even so, I'm going back through today and making sure of that fact.
You might want to consider doing that too, if you're a blogger.
What are the odds you get zinged? Small.
But I'm sure the 13 year old girl who used Napster thought that too, right? (God, what a fiasco THAT was).