I agree, taal.
Who is monitoring that trend? It seems to be an assumption that gets thrown around a lot these days, but I've never seen any data showing that X% of workers prefer to work downtown. I agree that in certain industries and among the under-30 crowd, that's almost certainly true, but given that most of the GTA lives in the 905 and outer-416, one would expect a pretty large proportion would prefer to work closer to home. With regional centres like NYCC, SCC, MCC and Markham Centre growing in size, and with their improving transportation connections, I don't see demand for suburban office space declining dramatically. It might be lagging downtown demand, but that might only be a temporary trend related to the surging financial and resource sectors, among others (app developers, etc.). Obviously an office downtown can draw from a larger pool of workers (downtowners plus pretty much as far out as GO extends), but for certain industries this is not required, espcially if the industries are already established, like the software industry around 404/407.