Yep, one set of aux-inputs. So that's nice, ipod should plug right in. Also has 3 sets of outputs, I don't need to fade my stereo so I'm going to use one set for connecting to other boats, like Shawn's set-up.
It's really hard to find reviews on the MB quart deck, but it's identical to one made by Rockford Fosgate (who owns MB Quart). I've read a couple reviews on their stuff and seems to be decent quality, and a couple guys with the marine deck have told me they love it, and have had no problems. You can get them on ebay for next to nothing (but hold out for a while, I got mine for $199, brand new!!)
Anyway, I'll let you know what I think of it. It still hasn't showed up on my doorstep...so obviously hasn't been installed yet.
I found a product to hard-wire my ipod into my stock 4runner deck and installed that yesterday. It converts the cd changer inputs to use as an aux-input. But my car has been acting really strange since the install... and I can't toggle between the ipod, the radio, and back without turning my car on and off??? I have NO idea why. But the sound quality is as good as CD.