Yes, the Metro will service International City via Green line however its not expected to happen soon.
Green line is expected to be completed by June 2010 and then the line will be further extended by 11km from Al Jaddaf to International City under the Green Line extension project which is expected to be completed by 2014.
It will be four years or even more before International City gets its first Metro station, therefore the impact of Metro on International City prices cannot be determined right now. Its bound to have some positive effect in the future but certainly will not have any effect in the next year or two.