Without a doubt one of the slickest app previews we saw at WES 2009 was for the 7digital MP3 Music Store for BlackBerry app, built by Develop IQ. The 7digital MP3 Music Store makes it easy to browse, buy and download DRM-free MP3s right to your BlackBerry, and the app is both sexy and smart. Example - if you're in cell coverage, you'll get a low-quality version of the song you want, which will then automatically be replaced by a high-quality version when you're in WiFi.

The 7digital MP3 Music Store for BlackBerry should be ready to download later this month/next month in available markets. Be sure to watch the video above for an excellent overview and lots of details.