I looked up on this after the initial post, and sony has some 400 dvd/cd juke boxes that can be chained.
Personally, I have a netgear nas, that is not only network storage, but can act as a streaming server compatible with many appliances that can the display on your TV.
If you do go the digital route, I would suggest a NAS that does RAID 5 (so if you loose a disk, or need to grow, you can do it pretty straightforward without loosing your data). -- actually, I have 2 - a primary and one I replicate too so I dont have to go through the effort of restoring from physical if it went t1ts up... At one stage I did this between two locations, but then I'm messed up ;-)
The brands I use above are not endorsements, just what I either saw first or decided, at the time, to use myself. I would spend time looking around first before making any new purchases....
The nice thing about NAS('s), is that they can act as backup devices for your computers and other digital media too..