I myself visited the screencast one, only because that is the link you posted two days ago. Actually, not looking at the link, I thought it would take me to the gridmaker itself (for which there are no link at all).
If you ask me, flash should (yes should), die swiftly and in great agony, after first have been outlawed. But that is a different story.
My advice is to pick one outlet for the videos. It does lessen the options. But it would probably also lessen confusion for the viewers, and your burden to administrate.
Screencast and Youtube are not the only services out there. All have their pros and cons. I happily watch clips, but I don't agree to either license. So if I had anything to show, I'd shop around a bit longer. Of course, getting an audience to leave the comfort zone of Youtube, isn't the easiest thing in the world. Then again, if those watching the clips, get direct links from here, the effort is probably minimal ...