With an NVidia card, i'm pretty sure you do need 3d tv play software to get 3d Blu Ray playback on an hdmi1.4 display. You just don't need the entire 3d vision kit. If Powerdvd provides 3d playback now without the help of NVidia 3d tv play drivers, it is news to me.
(ok I read the link posted by nikonf5 and it does report that NVidia 3d tv play is not necessary for 3d Blu ray playback, only necessary for 3d gaming. It says that you only need the updated drivers, available free. That is news to me and I'm looking to have it confirmed. I suspect it reflects a misunderstanding and for sure other parts of that post contradict the report and say that 3d tv play is necessary. Many many of us here have been viewing 3d Blu rays with 3d tv play.)
Two ways to get 3d tv play. One is to pay for it and download it. The other is to download it and install it free if you already have the 3d vision kit's USB emitter attached.
With ati cards, it's another story.