I don't see lossless being sold on iTunes because of the size and demand for it. Yes, some of you love it, but I'll take the slight audio degrading of compressed AAC over the storage-hogging lossless format.
I do forsee some sort of iTunes HD music coming in the future. This could be encoded in Dolby 5.1 and/or DTS but yet still compressed like the audio on DVDs. If you have ever heard a DTS audio disc, you know how awesome that could sound. But I rarely see DTS audio discs anywhere.