Gulf Air CEO Samer Majali recently spoke at the Arab Air Carriers Organization about the airline´s plans for the wide-scale introduction of regional operations using regional jets. This year GF introduced two Embraer 170s and just recently a pair of two Embraer 190s. Currently the airline is evaluating the E-jets by Brazilian manufacturer Embraer, the new C-Series by Canadair or the A-318 by Airbus, all models with roughly 90 to 110 seats. The A-318 would offer fleet communality with the big A-320 fleet of Gulf Air, but is considered a commercial failure due to its high weight in comparison with the competitors, which offer "real" regional jets (as the 318 is basically a shrunk A-319). The C-series would only become available in the 2013 to 2014 timeframe. The carrier expects a decision until years end.
Here is a link to the original article in flight global:
http://www.flightglobal.com/articles/2010/10/25/348875/gulf-air-considering-three-types-for-regional-jet-fleet.html