A 30-pin extension cable will plug that vamp into any older iDevice, so it's still very much alive. I use it with an iPad from time to time and it's great.
I was thinking about taking it apart and removing the rubber iphone holder (or even cutting the lip off so that an iPod would dock nicely) as an alternative. It's too good of a device to babysit your 8-tracks!
Good point and nothing to loose by attempting a mod after I upgrade my Iphone 4. Although the 5S isn't exactly blowing me away with innovation, so I may hold on to my rig for awhile longer.