IMHO criticizing this map for its lack of spatial accuracy is sort of missing the point. It's not designed to be in the space dimension, it's designed to be in the time dimension.
The official itself is very good for determining location and the nearest T stop to various landmarks. If that fails, then Google maps is even better.
However, this map is damn good for easily and immediately visualizing how long it takes to get from stop to stop.
I'd guess from your comment that don't likely live in Boston or have spent very little time here.
The way the city is set up, the T lines basically just run out toward other stuff. Only when you are in downtown can you find multiple lines close so most of the time you have only one option if any.
Check this map out: http://mapsof.net/map/boston-metro-map#.UVnvrodOTYg
In NYC, you can usually walk to different lines quickly.
There may be express trains in Boston, but I don't know of any??? I don't use the T to commute, so maybe someone else knows?
There aren't express trains, but it would still be useful to have some weekend service posted, especially for the green line (of which there are 5 once you get west enough!).
Re:Boston Subway Time-Scale Map
by myke_cameron on Monday April 01, 2013 @05:58PM
(#5476225)
There ARE express trains, they're just not scheduled in advance (for example the b line goes express from bu east to Washington to make up for delays quite frequently).
The regular T map (http://www.mbta.com/schedules_and_maps/subway/) is also abstract, just not as usefully. It doesn't show where stations are or what's near them.
Also, in most transit systems, travel time can depend significantly on the time of day you're traveling. Express trains don't always run and the time between trains increases during off-peak hours.