According to Adobe, flash has the following penetration: http://www.adobe.com/products/player_census/flashplayer/version_penetration.html http://www.adobe.com/

According to Adobe, flash has the following penetration: http://www.adobe.com/products/player_census/flashplayer/version_penetration.html http://www.adobe.com/products/player_census/flashplayer/vers... Of course, whether or not you should trust this 100% is up to you. My suspicious self would venture to guess Adobe tries to quantify the total number of users who have installed flash at some point, rather than those who have it currently enabled. I have no idea, though, if there's a big difference in those two metrics. Much less scientifically, I would guess that anyone who has flash enabled, also has javascript enabled. Flash has more security implications, so I'm guessing most people concerned enough to disable javascript would have also disabled flash. Since javascript is also an included feature in essentially every browser flash has a plugin for (and some it does not), its "adoption rate" should then be at least as high. This is just an educated guess, though, and not the result of some scientific analysis.