Ok, where to start. . . . the dns 5000 and 3000 use high speed rom drives. . . .they are a completely different unit. . . .than say the velocity which is slightly older technology. To the best of my knowledge, and since everyone else is coming out with new mp3 technology, you can probably expect to see something. But not an upgrade on any existing products, cause even still with products like the 5000, there is only so much you can update, I believe at this point after adding all the upgrades including mp3 playback, there is no more room for any further improvements. . .
You can kick and scream all you want, but that wont give you an upgrade, sorry man, it's not as simple as inserting a disc and uploading a file, there's only one brand that does that and I have to give them a lot of credit for that, but at this time, it's just not practical to re do older technology.