You can connect iPod or cd-player to the tape input. BM3000 has both RCA and DIN connectors and actually you can connect two devices at the same time, fe. iPod with RCA- and CD-player with DIN-connection. But it might cause lower volume levels if both are connected at the same time, but you can have an iPod cable (RCA->3,5mm plug) connected to the BM and use it only when needed.
If you have more devices you can buy an external selector box with more inputs and one output to the BM. I have a BM3000 too (just playing!), and a selector box to connect a CD-player, cassette deck, an Elcaset deck and my MacBook to the tape input!
Bang & Olufsen - The art of controlling sound, picture and light