All I can say is, "About fracking time!" The existence of DRM on iTunes tracks has limited the number of songs I purchase, so this will result in more sales (and those sales will be for more money). Here's how it works: the current tracks all stay the same, but there will be a new offering where you can purchase a 256 kbps version with no DRM for $1.29. Albums are the same price, but use the higher bitrate and lack DRM.
Since DRM is usually cracked, I wouldn't pay more for a DRM-free copy. However, the price increase also comes with a doubling of the bit rate, which is worth a little bit more money. I think it will be difficult for Apple to know why people are buying the higher priced songs, because they are changing two variables and there is no control. But, I guess the reason won't matter if they are making more money.
This is not the only new feature. A few days ago, Apple introduced "Complete My Album", which allows you to buy a full album and get discounted the price of the singles from the album you already purchased. This is a smart feature to have, but I am disappointed that it only works on purchases that are less than 180 days old. Sometimes it takes me a while to discover I like more than one or two songs on an album, and I am less likely to upgrade to the album if I can't get the discount, so they are still hurting themselves here.
Something they don't have, but I would like to see, is a feature that allows you to buy the music video for a song you already purchased for just $1. Right now, you can buy the music video and song for $2, but if you've already purchased the song, you are out of luck.