Flash on OS X Lion

Adobe Flash Player is supported in Lion (Chrome works by using its own copy of the plug-in that you can disable) and Safari uses the Plug-in installed in your personal libraries folder:

~/Library/Internet Plug-Ins/

or in the system-wide libraries:

/Library/Internet Plug-Ins/

Lion, however, doesn't ship with Flash player installed by default (I'm not 100% sure because I haven't had Flash in a long time), but that doesn't stop you from installing it.

Head over to Adobe's FlashPlayer download page and select 10.4-10.6 as your operating system:

So as you can see there is not a 10.7 version yet, so there are some issues. At first it was said that Lion disabled the Hardware acceleration of Flash; Adobe later retracted that when they found out it was their own bug.

The final release of Mac OS X Lion (10.7) provides the same support for Flash hardware video acceleration as Mac OS X Snow Leopard (10.6). The previous “Known Issue” described in a tech note suggesting that video hardware acceleration was disabled in Lion was incorrect and based on tests with a pre-release version of Mac OS X Lion that related to only one particular Mac GPU configuration.

_{source: Adobe's Blog}

If you are brave enough, you could try the BETA version (used by developers) that is theoretically the version that will be released for Lion.

Those Betas are available Here.