what is the Fuel Mileage

Depends how hard you drive it :) average city driving 11 or 12 Litres per 100 Kilometers

and as an American Response to this i get 20miles to the gallon city, havn't done enough highway to know but i bet bout 26miles to the gallon

My ’98 Subaru Outback, with the 2.5L, gets an average of 21MPG, of a 50/50 mix of city/highway driving. Since you have a turbo on a STi, I would think you would get worse mileage; at the same time however on the highway you have a sixth gear to use, unlike my 5spd. Also I drive my car pretty hard, so my gas mileage is hurting because of that. So in the ballpark average of 20MPG.

I usually got 18mpg in mine 50/50 driving

Again an European answer, but maybe some more detail. My stock MY05 Euro spec STi will go down to 9 liters / 100 km on the highway, but in the city my average is between 12 - 14 l / 100 km. On the track anything between 30 - 50 l / 100 km. And finally on the autobahn a tank of fuel will keep an STi going for about half an hour  when driving against the speed limiter (250 km/h). That translates to about 55 liters / 125 km.