Read the excerpt from "Opening Ceremonies of the New York and Brooklyn Bridge" by Hon. Seth Low, Mayor of the City of Brooklyn.

No one can compute the loss of time ensuing daily from delays at the ferries to the multitudes crossing the stream. And time is not only money--it is opportunity. Brooklyn becomes available, henceforth, as a place of residence to thousands, to whom the ability to reach their places of business without interruption from fog and ice is of paramount importance. To all Brooklyn's present citizens a distinct boon is given. The certainty of communication with New York afforded by the Bridge is the fundamental benefit it confers. Incident to this is the opportunity it gives for rapid communication.

According to the details in this excerpt, the people from Manhattan and Brooklyn

will still prefer to cross the river by ferry unless the weather does not allow it.
will not be able to communicate with much more speed and efficiency.
will no longer lose opportunities due to limited methods of crossing the river.
will be more likely to live in Manhattan but work in the borough of Brooklyn.