I emailed Tassillo again today. His email to me was rather vague and I was getting mixed signals from their website. It doesn't look like they've ever had an interface that's worked with any Ford 6-Disc changer. Below I pasted what I initially wrote him, and his response...
From Me with subject line -iPod2car and the Ford Fusion SEL V6 with Audiophile system- : "Are you guys working on, or have you already come up with, an iPod2car interface that is compatible with the Audiophile system in the Ford Fusion? I’m really anxious to get my hands on one.. There is a lot of demand for such a product, at least in the fusion clubs I’m a member of ."
From Tassillo: "The piece that is designed for all the new fords should be available within 30 to 45 days."
What do yall think?
I wrote him back today: "I was pumped to hear that all of the new fords would have an iPod interface, but I must admit to my skepticism. I don’t think I’ve seen any of your products have compatibility with the 6 disc Ford changers in the past. I gave word to the Fusion club that you guys were going to have an interface for the SEL sometime within the next 20 days, but if something changes, please let me know. Thanks!"
He responded: "We are trying to tell everyone mid next month. The reason it is not compatible with the 6 disc in dash units is that it can either come across as SAT or CD-C. so not only does it help you it helps us."
Again, he's crossing his word up a bit so I can't tell if the "it" he's referring to describes the new part too...
I wrote one more reply: "In your below comments, I’m reading the “it” as a reference to the old version of the ipod2car interface, right? The new one will not require the SAT or CD-C buttons? I’m guessing it will use the AUX, or something like that? Sorry to keep bugging you, but enquiring minds want to know

and I don’t want to get excited unless I know what you are saying for sure."
I'm starting to worry about this guy.... His response didn't make much sense, nor did it answer my question: "I'm just saying that’s how the head unit reads it. you will only need the AUX button for this piece to work."