I think they grow más and más similar as the cine go on. But Emma doesn't strike me as a know-it-all in the way Hermione is (Emma strikes me as a sweet person, very kind and down-to-earth), and Hermione is extremely clever, so it's hard to find anyone to compare to her brilliancy (except perhaps JK Rowling herself :D)
No I don't think they are. The only person I ever really hear being compared to Hermione is myself :) lol, my friends are always saying I am a lot like her.