Ooh, hark at her 

You are of course correct (although anyone who plays Settlers of Catan can tell you 6 and 8 come up more than 7). Does it not become a bell curve when there are numerous available modifiers, some of which are more common than others? Or is it still flat?
It's always flat on a single die, you have to add the results of two or more dice to get a bell curve as it is a graphical plot of all the possible outcomes.
Re the Settlers of Catan thing:
On an unmodified 2d6 roll:
Probability of 7 = 6 in 36
Probability of 6 = 5 in 36
Probability of 8 = 5 in 36
so there's a 10 in 36 chance of rolling a 6 OR 8 (5/36+5/36) and only a 6 in 36 chance of rolling a 7, so statistically in a single roll of 2d6 you're more likely to get a '6 or 8' result than a '7'.
Don't you just love dice and probability
