Ok nonk, well I'm basing it on my experience in paediatrics and obstetrics and gynaecology, my reading and understanding of the research, and conversations with colleagues and close friends, one of whom is a neonatologist.
The comment about mothers being made to feel guilty is based on having seen and treated quite a few mothers with post natal depression, not helped by their feelings of guilt at not being able to breast feed.
The comment about class and breast feeding is well documented in this country.
The comment about most of the advantages of breast feeding being in third world countries without access to clean water is also well documented.
The correlation with formula feeds and obesity is not as clear cut as the advocates like to make out, and the effect also comes quite early on.
Don't get me wrong, there are advantages in breast feeding, but they're not as huge as some like to say, and there has been little proof of much benefit past six months, probably more like three months.