We could do the matt vs gloss arguement all day, I'm sure! I know you're right about matt sales, and I also know that a number of well-respected and renowned fine art photographers have embraced the DJ130 because they like the greater dmax of the gloss. For myself, I have prints (mostly B&W) that I prefer on matt, and those I prefer on gloss - there is no hard and fast rule as far as I'm concerned.
A colleague did a 16x24" corporate portrait last year and delivered it on Hahnemuehle Rag from his 4800. The client had seen the proofs on the website, and were disappointed with the print - said it seemed too flat compared with the on-screen proofs. He reprinted it on the DJ190 on HP satin paper, and the client preferred it. Seeing the prints side by side, the Epson was far better colour matched to the original (the HP was too yellow), but the satin finish had more contrast and was more 3-D.
I can't bring myself to buy the HP because I can't get a decent colour match from it, and next to the Epson it seems like a fragile toy. However, anything other than matt from the Epsons is frankly unacceptable due to the truly awful gloss differential issue, and (admittedly now improved) metamerism.
So I'm hoping for great things from this Canon. Hopefully they've weighed up the pros and cons of the HP / Epson competition and are about to deliver something to finally cause me to fill that LF printer-shaped gap in my workroom! DSLR domination today, printers tomorrow?!