cdu

I've been looking around for any firm description of what's involved with the 2005's DVD navigation system, but mostly come up short.

Bluetooth -- may or may not have it? If this particular car doesn't have the bluetooth add-on is it basically hopeless getting the thingy necessary to make it do bluetooth? Even if it did have the proper module, would it be able to do non-telephone things (namely streaming music / podcasts from my phone)

aux in?

It looks like you have a choice of the navigation disk *or* a music CD? Or you can put the MP3s on SDHC cards? (SD?) If it is just SD it is limited to 2gb?

I assume that up-to-date(ish) DVDs are either from shady sources or prohibitively expensive? Is the UI at all usable? I assume putting a backup camera is out-of-the-question? Do they all integrate into the instrument cluster? From reading the manual it looks like it can pop directions onto the gauge cluster's display, which seems like it might actually be pretty useful.

Are these things at all useful or are they just an interesting historical artifact? (I'm assuming that the radio / CD / CD changer part are just fine, but the other "Fancy" features aren't terribly useful a decade on)

Anyone with hands-on experience would be great!

Thanks!
Chris