Amazon's digital music store, Amazon MP3, is now offering songs administered by Warner Music in the DRM-free MP3 format. This gives the store 2.9 million tracks, and leaves Sony/BMG as the last major label holdout. Not bad, considering Amazon MP3 launched only in September and is technically still in beta.
Amazon also said that 2007 was its best holiday season since it opened in 1994--and it wasn't just a strong economy, as other retailers reported a generally weak season. But I don't know if Amazon's effectively using its traffic to promote its digital offering: when you run a search for an artist at the Amazon home page, audio CDs tend to dominate the search results, with downloads coming quite far down the first page.