SACD availability

SACD discs are mostly classical and jazz but there's still many older rock discs available. I think your best bet is to get a universal player that will play everything including DVDA and maybe Bluray and you'll have all formats covered for a while.

IMO Sony ONLY introduced SACD to stall DVD-A because they had Bluray in the works, and did not want the HD-DVD camp to have the DVD-A support..
Once Sony totally killed any hope for DVD-A, Sony basically abandoned SACD. This is my impression. Sony made players for awhile, but the Sony music never did really get behind SACD. IF Sony had really wanted to make SACD important, they would have made ALL releases on the Sony label in the dual format.
Now, the main supporters of SACD are small independent labels of classical and Jazz, which do not get carried in major mass market stores like Best Buy.
My personal assumption, is Sony may possibly go for Blu Ray music, If they thought it would be a winner. I think they will NOT do it because of hi rez downloads being more likely to take off. And becase Blu Ray has not dominated the market as DVD did when it came out. Plenty of folks (including myself) are just not impressed enough to go Blu Ray over DVD.

If you are primarily a classical and jazz listener there is plenty of music out there on SACD as well as new releases coming out. IMO I would not consider a player without SACD capability. But I listening primarily to classical and jazz so I have no problem finding music to purchase. And as Elizabeth points out it appears that only the small / medium size labels are supporting it.