Hmmm... I hadn't heard too much about this except for in connection with DirectTV etc. so I looked here as to what the story is in Canada:
http://en.wikipedia.org/wiki/Xm#XM_in_Canada
and I see it is indeed available here now after the usual "no, Canadians don't need this fight"... 
At the beginning of the article it says you can use Winamp to stream XM radio... but I'm not familiar with that program anymore... it's probably not free and not for Mac...
Question about AIM... can you install it to use for stuff like this while completely ignoring the "chat" features unless some sort of national disaster requires it?
This mentions the AOL account:
http://www.mac360.com/index.php/mac360/com...le_no_from_aol/
QUOTE
If you have an AOL account you can listen to the broadband streams of higher quality music. How much higher? I’m still trying to figure that out.