While the numbers, as presented in this article, would make it a much better deal to make a 19% down-payment and take on mortgage insurance rather than an uninsured 20% down-payment (particularly if you took the $4,500 savings mentioned in this article and used that as a lump-sum payment after setting up the mortgage), I would STRONGLY question the assumption of a 45 basis point spread that everything in this story is based around.

If that is indeed the case today it is a very new development, and I suspect it is far from universal.