The Sheppard extention to the east of Don Mills favours North York and Scarborough. One reason why Ford was elected is that the people outside the dt core are saying it's about time some resources are allocated to the area that's neglected such as the Scarborough RT. By extending the subway line right across, it'll make more sense for higher end investments from the private and public sector surrounding it, a lot more people will end up riding it since it'll be more convenient.
Well, with all due respect to the people living in North York and Scarborough who are saying that, they're wrong. The last subway built in the Old City of Toronto was in the 1970s. Since then, every subway expansion has occured in 'suburban' Toronto. I'd say the suburbs has seen a disproportionately high percentage of transit dollars in the past 30 years or so.