I have to worry every time Adobe makes an acquisition. Seldom do the products improve.
Though the adoption has fallen, ActionScript 3 was a near strict improvement over 2, and it was released a good while after the Macromedia acquisition.
There were public betas available about 6 months after the acquisition, which didn't leave Adobe much time to change anything. Even the main APIs, like those in playerglobal.swc, almost all have a copyright stamp of 2005 in them.