Hey,

take a look at the mp3 patents:
http://www.tunequest.org/a-big-list-...ents/20070226/

If you were an IPR lawyer, you will have to be cautious about the issues, right. So, take a look at those patents and say that you would be certain that OGG doesn't infringe any of them and that it won't infringe any patents for aac or wma. Heck, there must be tons of other codecs with similar patent portfolios.

Now, consider that you choose mp3 now. You pay the price and you are safe. Most of the internet revolves around mp3s anyway. Also, what you will be certain of, is that it will be completely patent free within 10 years and that for the most part it will be patent free within a few years. Some of the later acquired patents don't really affect the normal mp3 playback but some special uses of it (like the theatre 5.1 audio in mp3 patent).

You can read the instruction on patent expiration from here:
http://answers.google.com/answers/threadview?id=2434