Canon Pixma Pro9000 II or Epson 2880

I realize I may be trying to compare apples to oranges here but I would like to field some opinions from the POTN audience.

My guess is the Pro9000 II will be good and perhaps better for color photos (it has more shades of ink versus the epson), whereas the the 2880 would be better for B&W due to the 3 black/gray cartridges (Photo K, Light K, Light Light K or Matte K, Light K, Light Light K). The Pro9000 only has the option for matte black or photo black. Will there be significant differences in the quality due to the DPI differences too?

I'm debating if I want to keep my Pro9000 or sell it and perhaps pick up a 2880 instead.

Thanks!