If you don't want to chew up a heap of data after streaming the previews over and over, you can save the direct files of the previews to your computer and add them to iTunes.
1. First, go here:
http://itunes.apple.com/gb/preorder/...py/id474070094
2. On your browser, click on 'Page Source' or similar depending on what you use.
3. Use the 'find' option and type in
.m4a into the field.
4. You will see a direct link to each file with
.m4a on the end. If you scroll a little way sideways, you will see the song title.
5. Copy the link and paste it into your web browser. There will be a media player that plays the file.
6. There should be an option somewhere to 'save as source' etc. Save it.
7. The file appears as a bunch of random letters. Change it to the song title. At the end of the file, delete
.aac.p and replace it with
.m4a and then open the file.
8. Listen to the song preview in full iTunes Store quality.