I have had the same problems, except, using Adobe's recommended installer it goes to 97 % before stopping.
I have uninstalled the old version as recommended and I have tried the alternative installers (one for Safari and Firefox and the other for Opera and Chrome). For those the installer stops at 95% rather than 97 %.
In checking each it appears that the flash player did install on Chrome so I am able to view Flash applications using Chrome, at least. This has to be a compatibility problem within the new Flash Player and Adobe should fix it ASAP! Knowing Apples attitude about Flash I'm sure any fix won't come from that direction.
One individual recommended shutting down everything but the flash player updater and then trying installation over and over until it eventually gets a complete install. a reply to that indicated that it worked for one individual. But that method has not worked for me!
So long as flash based items are posted to websites I guess we are crippled until Adobe provides a fix!
Opps! While typing that last message I was trying another install and I just noticed that it was successful.
I guess persistence may still work!!!
Cheers John, though persistence has its limits right now!
And just as I wrote that mine too installed! Maybe we're onto something here?!!!