The further east she turns, the more oil platforms in the Gulf are in the direct path of the storm.
Thus I must admit I'm a little surprised that the markets have been reacting to the eastward shift in Rita's path positively. Crude oil on the NYMEX is down to $64.80/barrel at latest. Reaction seems to be driven by confidence that refining capacity won't be damaged due to the storm's weakening to Category 3 status rather than any concerns over post-Rita production capacity.
The only thing that is certain at this point is that folks in Port Arthur had better get out or hunker down.