A Nostalgia Act?

I've been reading some of the on-line chatter regarding KC's Live in Toronto with great interest, especially the stuff at Progressive Ears. (I haven't got the album yet but, trust me, I will be doing so.) Broadly speaking there's a debate between those who regard the latest 7-man incarnation of the Crimson beast as a nostalgia act, re-enacting past glories for fans who want to dwell in the past rather than going forward, and those who see the band as a manifestation of the great Crimson tradition of forever moving into new territory in its radical re-imagining of the past. Based on what I've read about the actual concerts performed by the line-up, and the little I've actually heard of them on Live at the Orpheum, I find myself in the latter camp, but not to the point that I don't grasp what more critical voices are getting at. (I think the somewhat negative review that features in the first segment of the link above is a thoughtful and measured piece even though I think its criticisms are fundamentally misplaced.)

It seems to me that there's are some fascinating questions behind the debate, the first and foremost of these being whether the music of the popular culture of the twentieth century can survive as living art into the future, and, if so, in what form? Will a repertoire emerge, in relation to those forms of music that lend themselves to distinct structures, and will this become the basis of live performance?

If such a repertoire were to emerge I think something other than nostalgia might be at work. I don't think we listen to, say, Beethoven as a kind of legacy from the past to which we're simply paying homage. And I don't think we need make the assumption that every musician playing material from a back catalogue is indulging in a kind of comfortable nostalgia. Perhaps the acid test lies in the nature of the experience for the listener? If you're hearing something new and urgent then the music belongs to the present rather than the past regardless of its provenance.