what was the original file you uploaded? mpg? increase to 40% :) video looks nice, but you can defnitely see the blocks. 4 or 5mbps will make it look nicer.

you're shooting with an hv20 right? when you dump the footage from the hv20 to your computer, they should be raw .mpeg or .m2t files depending on what you use to capture. i use HDVsplit and they come out as mpg .m2t files which is raw raw and encoded by the camera. i'm sure you're not using this to upload :)

what program are you using to edit/encode? in most programs, you shoudl be able to export to quicktime/mp4/windows media(wmv) using bitrate of about 4-5mbps instead of a percent. eugenia has some good tutorials here if they can help you. i just want to make sure you don't lose quality especially if the blocks are showing up in the original encoded file. i see the blocks mostly in the darker and pan shots (quick movements or scenery changes). i downloaded the original file and see it in windows media player as well as the flash above. in order for the flash video above to come out decent, the original footage uploaded should be decent as well.

here is eugenia's guide:
vimeo.com/forums/topic:3671