Canon sent me an ipf6100 which I set up today and started playing around with. Thought I would post a couple of early observations.
The setup was straight forward and not too challenging. The paper canon sent me has no matching paper type in the printer nor a profile available. I printed some initial test prints which don't look too great, but that's to be expected for now. I do feel there is a little improvements in the blacks. I need to find some old prints I made with the ipf5000 before I gave up on it to compare them.
The roll feed unit performed very well ... 0 skewing errors in about 20 unload/load cycles. I don't know if this is due to the 6100 built in unit vs the 5000 "add on" unit, but since the 5000 now comes with the roll feed I would assume it functions similarly (my 5000 had some real problems with loading rolls). I really like how easy it is to load a roll of paper.
While the printer "warns" you that your selected paper type doesn't match what you set in the driver, you really can ignore it. It appears that the driver setting overrides it, so you have to get it right when printing through the driver, but the printer warning simply shows up on the LCD screen but doesn't interfere.
The included ethernet is a nice add, but using Bonjour on the mac to connect has been somewhat buggy ... if the printer goes "offlline" , a few times the only way I could get them to talk again is to delete the printer from printer setup utility and then recreate it. Simple and not very painful, but a nuisance. Hopefullly I can find out what I might be doing to cause this. I will proabably change and using CanonIP and hard code an IP address into the printer, instead of using Bonjour.
There are 10 "special" paper types, which give you 5 different ink densities of both mk and pk inks. For many non-Canon papers it appears using one of them is the best option, but I'm not sure how they handle things like paper thickness.
I'll have a profile created for Kodak Premium luster and some good test prints by tomorrow to compare it against my 9800.
Overall I must say this experience is going far better than my ipf5000 experience did. Partially because its the second time through, but there are some improvements.