Unfortunately, while the changes that are going in the game will be helpful. AbleGamers points out that the game isn't perfect for those with colorblindness yet -- mob levels are often shown to the player in a certain color, and there's no option yet for players to see that information in any other format. Additionally, Rogue combo points are shown by filing those little circles in with colors, and colorblind players who aren't able to see that color will have difficulty with that mechanic as well.
The good news is that, while Blizzard does want to make sure their core game is as accessible as possible, there's lots of room for addon authors to do more. Colorblindness is surprisingly prevalent, and everything coders can do to make the game easier to play will be welcomed by those who need it.