Is there a flash player that could handle all of the formats mentioned above. Or different players that could handle it?
http://www.adobe.com/devnet/flashplayer/articles/hd_video_flash_player.html explains Flash 9's h.264 and aac support. Presumably Flash can play aac audio without h.264 video. Someone wrote an ogg vorbis player in Flash (http://drawlogic.com/2008/10/04/as3-fvorbis-flash-ogg-vorbis-player/) and the performance was acceptable. It's not written in ActionScript. It's written in a different language that compiles to Flash-compatible bytecode.
If you want to play wma, look no further than Silverlight. http://silverlight.net/forums/p/2786/7569.aspx lists all the supported codecs. Silverlight 3 also allows you to write your own audio codecs in managed code.
JOrbis is a Java applet that can play ogg/vorbis including internet radio.