I have the 11 flash working (nvidia 8200 integrated + 270.26 drivers, Debian Squeeze 32-bit, Opera 11.10 browser).
Description: Shockwave Flash 11.0 d0
Check the attachment. Test subject:
!! The real hw acceleration can be seen only after the whole video is cached to disk!!.
The caching process eats lots of cpu cycles it seems.
Until then i had 50% operapluginwrapper and 38% Opera processes, after it cached completely i had 20-30% operapluginwrapper and 2% Opera processes.
All this with 1080p and the larger video size (not fullscreen).
Hm. It does work for me. Hardware acceleration, 1080p with Opera 11.10, flash 10.2.152.27 on Debian Squeeze 32-bit nvidia 8200 + 270.26 drivers). After caching ~18-25% CPU
The screenshot is taken with the 11 d0 flash. The tearing is not visible while playing. Also, there is no garbage on the screen as with the 10.2.152 version.