I have watched flash video successfully on justin.tv, though it crashed the whole smart hub after a few minutes-it ran through however much memory the tv has I think. And sound worked too; you'll see some reviews where flash video worked, but without sound. That must have been fixed in a firmware update, because i had sound last time i tried it. Again, i think the limited memory will be your bottleneck more than anything. I didn't try Netflix in browser, so no clue about silverlight.