And nfitz, did they have any off-peak or daily ridership projections? The reason I ask is:
1) Malls are generally not peak generators. If the movement of the Mississauga bus routes from Islington to Sherway was not factored into that 700 pphpd number, that could account for the low number. Generally, malls get the bulk of their usage from noon to 7pm on weekdays, and 11 to 6 on weekends. Peak hour numbers are usually done for morning commutes as well, and nobody besides those working at the mall would be going to Sherway at 9am.
2) In 2001, the condos around Sherway wern't there. Those condos could potentially add a thousand or so commuters.
3) I bet they didn't also factor in a Don Mills-style Park n ride lot, which could potentially syphon off another couple thousand drivers a day off the Gardiner/QEW.