Regional breakdown of MySpace and YouTube audiences
MySpace has a bit more users, at about 85 to 75 million judging from the graphs. But Myspace traffic is about 92% from North America, and almost all of the remainder from Europe. YouTube is much more evenly split, with its largest usage from Asia about 38%, then Europe 32%, then North America 28% and the rest of the world splits the rest.
I can't find the original content on FT.com (and, hey, it'd be pay-walled anyhow) but I'm sure Mr Moore is a reliable enough secondary source :-)
It is testament to the power of YouTube's platform that it has spread so far and wide. Also bodes well for future growth of users / community.