Apple today announced the first anniversary of its iTunes Music Store. “In its first year, music fans have purchased more than 70 million songs, making it the number one online music service in the world with more than 70 percent market share of legal downloads for singles and albums,” says Apple in the press release. “iTunes customers are currently purchasing 2.7 million songs per week, a rate of 140 million songs per year.” The press release also discusses in some detail, iTunes 4.5 (released earlier today), or what Apple calls the “third generation iTunes Music Store.”