One of the main reasons for the 717 not being flavour of the month in Europe is its weight.
On the apron, its Aircraft Prepared for Service (APS) weight is some 5 tons greater than the AVRO RJ100 to carry around the same number of passengers.
Since in Europe most of the navigation, takeoff, landing, parking and handling charges are weight related, the extra cost per passenger seat mile would be noticeable particularly if you are operating 8 to 12 sector days.
It is definitely faster than the RJ, but over the sector lengths envisaged (mostly below 1 hour) the impact of this extra speed would be negligible. As to fuel burn, I'm not sure. However, I would expect it to be lower than the RJ.
At one time Boeing were trying to reduce the aircraft basic weight but this seems to have come to nought. Their was also talk of an extra flap setting to allow it in and out of LCY.
I seem to remember reading an article stating that if BAE Systems had not cancelled the RJX programme, the 717 would have been binned by Boeing.