yes, confirmed in hardy, choppy playback in youtube (in fullscreen mode) for version 9,0,115, Big CPU usage.
Does not happen with last version v9,0,48
had to downgrade.
Intel Core 2 Duo 2,0 GHz and 2gb ram
extremelly slow on athlon 2.0ghz 512mb ram. Again v9,0,48 works really well in this setup too.
seems hardware acceleration does not really work in 9,0,115 for linux. In windows speed is fine, even in FF under wine.
also, swfdec (last version, not one in repos) seems to work well. Would be a good candidate to substitute gnash or include it as extra option. Since we can't redistribute flash, swfdec might be a good alternative for the population with slower PCs and UMPCs.
Really worth looking into this problem, as some people only use linux to "surf" the web and the slowness will sure disappoint many thanks to adobe :(