OK, now that I've vented a little and had a chance to think about it a bit, we really don't have any concrete info yet, just rumor at this time. Possibly pre-mature for any 555ES Hot Rod hurling.
Upon reflection, this is really less drastic than when Sony switched from 2-channel SACD (all first-gen SACDPs only played back 2-channels) to the newer multi-channel units. This made all previous 2-channel SACDPs (SCD-1, 777ES, 333ES) basically obsolete. But of course newer multi-channel discs still play back on old 2-channel machines as the multi-channel discs have a standard 2-channel hi-rez mix on them. "SACD2", *if* it is as rumored, seems to me to be less of a change-over than it was when they added multi-channel capability. If they can make multi-channel discs backwards compatible with 2-channel machines, they can find a way to add video without making them unplayable on today's SACDPs. Also, the article does say that the ability to add video has always been in the spec, so it's not like they hadn't thought ahead about this when they first released SACD. This therefore should not require some whole new re-architecting of the SACD for SACD2 that will prohibit backwards compatibility.
I doubt Sony are complete morons, it's not like they live on some other planet and do not understand us humans. I'm 99.999999999% certain that *if* there is an SACD 2 it will be backward compatible with existing SACD players.
In the receiver market and DVD player market, they are constantly adding new badges to the front of the player to support new audio standards that do not prohibit backwards compatibility (Pro Logic 2, Dolby EX, DTS ES, etc.). There's no way Sony is going to be stupid enough to obsolete SACD as we know it today with SACD2.
I think realistic worst case scenario for SACD 2 are the following:
1. Audible watermarking for enhanced copy protection as they do on DVD-Audio. This is a very low level sort of "noise" that is introduced to make copying impossible, but some people claim this noise intrudes into audible frequencies on hi-rez discs.
2. Loss of resale value on today's standard SACDPs. OTOH, SACDPs without a video section will be more "audiophile", as video circuitry needed for SACD2 can introduce noise to the player. This may make older players without a video section somewhat more desirable, but that's probably wishful thinking. In any case digital sources lose lots of their value fast precisely because things change so rapidly in the digital world.
3. SACD2s will require you to hunt through on-screen menus to select the desired audio track. This will only happen if SACD2 discs are not backwards compatible at all with current SACDPs. I don't think that's very likely at all.
Mark