I think she looks great for the part! Bella is just an average teen age girl, she likes to keep things simple, low-maintenance, forgoes the girly look at all costs, and she's smart (for the most part). And this girl seems to give out that vibe. It would be hugely disappointing to see some model-esque blonde chick cast into the part!
Also, there are some rumors running around about Edward. Go here to see what they are saying.
So, what do you think of Bella?