For the entire sordid tale, (particularly Janet Smith's Response and Ronald McArthur's Response) see the timeline of the controversy at the Seattle Catholic web site.
My conclusion is that Humanae Vitae is to Castii Canubii what the Novus Ordo Missae mass is to the Tridentine Latin Mass, i.e., yeah, its Catholic, and it teaches Truth, but like the new mass, it ain't always pretty, and it ain't necessarily an improvement on what came before it.
The fact that the two most significant acts of Pope Paul VI were the promulgation of the New Mass and the publication of Humanae Vitae, somehow links these two important developments in my mind.
The poor theology related in the vernacular translations of the Latin (but not, necessarily in the Latin itself!) of the Novus Ordo Missae has lead to decreased belief in the Real Presence, and decreased awareness that the mass IS the Supreme Sacrifice. In my opinion, it also increased the rate of falling away from the faith that accompanied this post-modern, post Christian moment, ushered in by the sexual revolution, which in turn was enabled by the introduction of the Pill in 1959/1960.
So a critical examination of Humanae Vitae is indeed a legitimate endeavor, and in such examination, if Humanae Vitae seems to come up lacking, it is still no less authoritative than the new mass itself, if we are to believe the Gates Shall Not Prevail.
Of course, the result in theology has been particularly dramatic, since it has reduced what was a science to a mere feeling. As american_colleen said, it's now become "Jesus is our friend" garbage, babbled about by people who should know better.
Given the current uproar in the church, couldn't someone with a less ... incendiary name have been found to make this statement?