I took a test shot of a pillow with a detailed semi-photo realistic embroidery on it with my 7D and then compared it zoomed in on the back of the camera to the pillow, and my eye could not see hue or saturation shifts that were not being captured by the camera accurately.
If you want to know what all the fuss is about, compare the pillow to a print of the photo of the pillow instead of the back-of-the-camera preview. I guarantee you you'll see differences.
If you were doing portrait photography and your model had posed with the pillow, I can all but guarantee you that you wouldn't give a damn about those differences, so long as the model's skin looked good.
And if you took a picture of the pillow to sell it on Ebay or to email to your family, it'd also be just fine.
If you took the picture to include in a product catalog, depending on the client, it might matter or it might be "good enough."
If it were an oil painting instead of a pillow and you were making giclee prints to sell at a hundred bucks a pop for an 8" x 10", it would not be "good enough," though there're those who'll still try to pass it off as such.
And if it were an oil painting that you were recording as part of a preservation effort for a major museum, you'd be laughed out of the room.
For the overwhelming number of users for the overwhelming number of situations, modern DSLRs have unimaginably fantastic color reproduction just as they are. For the overwhelming number of the remainder of users for the overwhelming number of remaining situations, modern DSLRs can be made to function to superlative standards, if you know what you're doing. And, for a very tiny fraction of a percent of the population, modern DSLRs are a toy when it comes to color reproduction.
Me? Most of the time I'm in the first camp, but I spend a significant amount of my photographic time in the second camp. And I'm positively thrilled with my 5DII and I'm in the process of getting my 5DIII all dialed in and anxious to see how well it does. I'm pretty sure that the 5DIII, more importantly combined with some enhancements to my workflow that I'm working on at the same time, will let me actually get some results that might start to rival the stuff they do in major museums -- maybe even good enough for minor museums, which could open up some really interesting possibilities for some really fun gigs.