I can play flash videos locally, in chromium, and in epiphany (the GNOME web browser). For some reason support is spotty in firefox. Youtube will play most of the time but sometimes the video loads in a much smaller frame. Other sites with flash video or flash games rarely load. Occasionally the very same page will fail to load but succeed on refresh. Other pages will give me a link to install flash player. I can't find a pattern at all. I suspect a plugin conflict but looking at the plugin manager in preferences, I don't see one.
Ubuntu 11.10 (32-bit and 64-bit) flash 11.1