My opinion? This would pretty much kill the iTunes Music Store. I'm already reluctant to buy music via iTunes because of the included DRM. If they increase the price, I'll stop buying downloaded music altogether and go back to buying non-DRM CD's. I'm certain I'm not alone in this opinion.
Just the other day, a student in one our labs wanted to use a song she had purchased on her computer at home (using iTunes v6.0) for a presentation she was creating for a class project. Our lab computers have iTunes v4.9 on them and songs purchased in iTunes 6 don't work in previous versions. If I had not been there to help her burn a CD and then re-rip it back to a non-DRM MP3, she would never have been able to use the song she legally purchased for her presentation. The conversion process to get rid of the DRM so she could use the song as she wanted was just too complex. She was cursing Apple and the iTunes store and I had to explain to her that it's the large music companies forcing DRM, not Apple. And now the greedy jerks are whining about profit and forcing Apple to increase the prices on much of their music.