Seattle-based Amazon.com said today that its MP3 music store will be pre-loaded on the T-Mobile G1, the new cell phone based on Google's Android open source mobile phone software. According to Amazon, the T-Mobile phone will allow users to search for, download, and buy Amazon MP3 music. Financial deals of the preload were not disclosed. T-Mobile's US headquarters are in Bellevue. T-Mobile is launching the G1 today.