[link|http://www.wunderground.com/tropical/tracking/at200704_model.html|Computer Model Hurricane Forecasts for Dean] at Weather Underground.
The trouble with taking averages is that some of the paths may be much more likely than others based on previous storms. Apparently a lot will depend on how things are when/if it enters the Gulf of Mexico.
There's a neat little animated model [link|http://www.wunderground.com/tropical/tracking/at200704_v5d.html?extraprod=v5d#a_topad|here].
Cheers,
Scott.