I think it's wrong to copy someone's actual work and pictures word for word. I used to teach and would have kids get so upset when I gave them a zero for turning in someone else's writing as their own.
BUT I don't think we can be too upset if someone blogs about the same subject we chose. It's NOT a contest and there are tons of ideas out there just waiting to be shared. Unless you are trying to make money by bloggiing, it's really a labor of love isn't it?
I can pull up hundreds of ideas in seconds by using search tools like Google and so can everyone. It's just nice to have a bunch collected in one or two places, but there really are no limits!
Someone posted about pinterest.com. What a fabulous idea!
Repinning someone's interest is encouraged and it just keeps the idea shared and reshared!