Heh, I was contemplating creating a topic like this a while ago, but figured I wouldn't get many replies so I gave up on that idea.
Back on topic... I'm assuming the end of disc-based media will happen when we switch over to digital distribution over the Internet completely - which won't happen in several years to come, given how the development of network infrastructure is kinda slow in some of the primary markets (think the US). I couldn't wait for it to happen, I hate discs, I've got about 10k discs (no joke) and I couldn't possibly keep them all in store. Compared to having stuff stored on hard drive, where it's searchable and won't deteriorate (because discs do deteriorate over time), having it on disc(s) is inconvenient.
Edit: regarding consumer media on solid state memory... that's still rather expensive to produce, especially if you want it to be fast enough to allow for decent data read rates, so... not likely for a very long time -- as mentioned above, it's more likely we'd see fully Internet-based distribution before consumer media on SSD.
I'm actually hesitant to buy boxed games these days as I find the disc format a major inconvenience. Steam is a godsend, in a sense.