With the Nokia N900 offering full support for Adobe Flash in the browser, why couldn't the Nokia N9 have the same feature? Thanks to the development of a Flash plug-in for the MeeGo version of the Firefox browser, the Nokia N9 will now have a browser that supports Flash. However, the default browser and other third party software for the N9, like Opera Mobile, will continue to not support Flash. It should be (and now has been) pointed out that the plug-in was developed by "Nokia People", not those associated with Adobe or Firefox. The confirmation comes from a post made by a developer working for Nokia, who posted on the Maemo.org Community forum. The message adds that the MeeGo variant of Firefox has been "Adobe Flash" certified.
Source : Phonearena