I don't think anyone will lose interest. Yeah, Jon produced it, but the band is Witherfall, and they played on the record, and as far as I know, wrote all the material.
I don't know the ins and outs of how involved Jon was -- did he mix it? Did he engineer the sessions? If all he did was produce it, then I don't think people will care.
Personally, as much as it pains me to say, I can't support anything Jon has a major hand in creatively going forward (IE or D&W). I can't say one thing, and then say another with my wallet. But the Witherfall record is something in a different category, at least to me.