PS... not a knock at vholdr -- both cams (vholdr and gopro) have their pluses and minuses. The gopro is clunky looking and has a harder to use interface. They both have different lens angles. The vholdr has some issues with its response to vibration (say mounted to mtb handlebars, for instance).
If the OP is considering a POV (point of view) camera like the gopro or vholdr, I'd head over to mtbr.com (mountain bike review) and read through some threads in the videos subforum to get an idea of what I'm talking about.
For a regular hand held cam, it's hard to beat the canon vixia hf r100
One thing to keep in mind is that while hd video is cool, it's also more resource intensive. You may find that your $300 camera leads to a $1200 computer to edit the video.