So I got my Hv10 today only to discover a pretty obvious "hot" green pixel on low light footage.

Two examples below:

http://marty.id.au/content/photos/dot.jpg
http://marty.id.au/content/photos/dot2.jpg

Is this something the warranty should cover? It's visible on daylight footage as well if I look hard enough.

Yes, looks like a bad pixel, take the camera back and get another one.