This got me curious, so I spent some time looking around the Nexus 7 webpage. It says that Flash IS supported, just not in Chrome. The note says that you can download Browser from Google Play. Presumably, other browsers with plugin support (Firefox 14) should be compatible as well.
Chrome for android does not support flash and according to Adobe, it won't. Apparently you'll be able to download the usual default browser on the play store if you require flash, or an assortment of 3rd party browsers that support flash.
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