It's usually just down to limitations of the software you're trying to use. Most of the software you mentioned above is just coded to look for simple web cams, or old-school analog devices that output (standard def or lower resolution) raw video frames. The HDPVR outputs high definition H.264 video, and these apps dont know what to do with it, so they dont list this device as an option. There is nothing to stop these applications from using this device if they wanted to, but they'd need to be updated to handle the H.264 input.
There is other apps besides TME that support the HDPVR, and more appearing all the time. You can use PVR apps like NextPVR or Mediaportal, or if you wanted to stream to justin.tv or ustream you can use xsplit etc.