I don't see this being successful, at least not among audio files. Apple currently charges $0.99/track for lossy audio, it stands to reason that a file many times the size will be more expensive to store and distribute; it wouldn't surprise me to see these lossless files going for $2.99-$3.99 per track.
At that price it's not attractive to the regular iTunes user, their systems can't resolve the differences between lossy and lossless compression, therefore this feature is almost useless among their existing client base. Secondly, audiophiles who spend thousands of dollars on systems are typically going to want more than one track, and if they are willing to put down $500 for a pair of headphones they are likely willing to put down $15 for a CD containing ALL of the music, free of DRM.
What audiophile is going to want to pay a premium for a track locked down in a format he can't transcode, manipulate, etc... to me the value just seems really low. I have no problem spending money, but I'd rather spend slightly more to get a whole lot more ie, buying the CD and ripping it myself.
Not to mention that if your hard drive should suddenly decide to take a dump you can't exactly re-rip your CDs if you don't have them to begin with.