I read the book a couple days ago. My second time, first being before the LOTR movies came out, though I had read the graphic novel years before that.
I found it interesting how I didn't insert any of the movie actors in my mind while I pictured the characters, rather reverting moreso to how they looked in that graphic novel. Generally more cartoony representations, considering that's how the dwarves were described, at least. Just a color tacked to a tunic and a pointy hat for each. I sorta find the "realness" of the movie offputting now, after it. The hobbit is much more fun to me when the dwarves all look like David the Gnome, and everyone's just having a gay old time.
I did like, though, how the goblins in the movie were less like the LOTR orcs. After reading the book again, and perhaps this is also due to reverting to graphic-novel imagery in my mind, I picture the goblins as less humanoid. More crouchy, smaller, less obviously "dudes in makeup." A little more gollumey. I think the movie did a great job changing up their look, it makes the LOTR orcs (and those second-in-command goblins in the Hobbit movie) look positively silly to me now.
And gimme Gandalf with silver scarf and big black boots, dagnabbit!