Now, ignoring the issue of general lj censorship, I can't really see a problem with that. Boobs with men attached are wrong, but boobs with babies attached are ok? I think not.
There's the start of an argument that breasts are designed for feeding babies, but they also serve as secondary sexual characteristics, and play an important part of sex - that's not stopped by the fact that there's a baby in your picture.
I find this and this equally obscene - how obscene is irrelevant - they fail to seriously offend me equally.
Just my two cents - I'm not gonna start on a tirade if there's a flood of breastfeeding posts, I'll just scroll my friends page faster.