I usually download everything I watch on Giantbomb and then pack it up on my Zune to watch somewhere else. I've been doing this for a few years and haven't had any problems.
It looks like the staff changed the sizes of certain videos though and maybe the format? Any video in the past month is a little lager in the "high" quality option and is taking forever to convert and sync. The old format for "high" would just transfer to my Zune in a few seconds, but now its having to convert it. Just wondering what was changed and if there's any way around the conversion?