Filed under: Portable Audio, Portable VideoBased on today's earlier leak of some weekly NPD marketshare data, we had our doubts that Apple had actually overtaken Wal-Mart as the number one music retailer in the US, but it looks like that January surge of iTunes gift cards and new iPod owners pushed it over the top for good -- and now we've got the PR to prove it. Apple's giving out the same "4 billion songs to 50 million customers" numbers as it has for a while now, but it says iTunes was the biggest game in town in January and February. Of c
