@Seth - you were asking about cam performance on the pi - evidently SOME cameras support h264 as an output format directly from hardware... at least the gst v4l2 video source things so:
video/x-h264, width=(int)[ 1, 32768 ], height=(int)[ 1, 32768 ], framerate=(fraction)[ 0/1, 100/1 ]
ref http://gstreamer.freedesktop.org/data/doc/gstreamer/head/gst-plugins-good-plugins/html/gst-plugins-good-plugins-v4l2src.html
might be worth looking in to what camera you get so it doesn't have to do any transcoding in software...