
Pointless...
Although G3s will get this update I can assure you it is pointless, I have the last generation iMac with a 600Mhz G3 and it can't run flash, it barely manages DivX or XviD with out dropped frames and skips.
Adobe will end Flash Player support for Apple’s aged PowerPC-based G3 machines after the release of version 10.1 of the software, which isn’t expected to land until early next year. Beyond Flash Player 10.1, Mac G3 fans will no longer be able to run the software on their computers. "The Adobe Flash Player 10.1 release, …
The Power Mac G3 dates from January 1999... just short on _eleven years ago_. In those days Win98SE and WinNT4 roamed the landscape... It has a maximum (supported) OS of 10.2.8. (Think Win2K vintage...) If you put XPostFacto on a G3 you could run 10.3.x, but you might not like the results. (I certainly didn't. I put 10.2.8 back on in very short order.) Running 10.4.x would be painful, running 10.5.x out of the question, and 10.6 runs only on Intel. I'd say that Flash support on a 11 year old machine would be the least of your problems...
And, yes, I have a beige G3. 266 MHz. 768 MB RAM. (officially Apple supported 192...) 6 MB video RAM using a ATI Rage card. (Yes, 6 whole MB video RAM, it shipped with _2_ MB...). I've replaced the original 4 GB hard drive with a slightly larger 80 GB drive (note that it's impossible to install OS X onto a partition larger than 8 GB on a beige G3, to install the OS I had to put the drive onto another, newer, Mac and run the installer from there; it'll run just fine once installed but simply won't install). The only browser I have on that machine is MSIE 5.2.something, and I've not even tried to access the internet from it for _years_. I suppose that FireFox 1 might work, if I could dig up a copy...
I have this vision of trying to watch a YouTube vid on it....
I don't think I have ever encountered a cpu max out on a Mac Pro with Flash
See
http://www.pixentral.com/show.php?picture=1peJCIXNfc97o07qQh9sGmJp7fWkt
based on
http://cde.cerosmedia.com/1P4b0fecab04899293.cde?exp=direct&jumpid=em_r2515_uk/en/hho/psg/giftguide_hhoemail-em-edm-pu-1223_extra/chev-hpstore/20091211
A very interesting and intuitive use of Flash if one may say so.