Comment 2 for bug 380501

Your comment is completely right.
I am using gsview32 4.9 + ghostscript 8.64.
The behavior of the viewer is as expected. The eps doesn't contain page size information, so gs displays it on whatever a page size is currently set in gsview.
Importing the eps into another program will in most cases clip the drawing to the bounding box, as you noted for MS Word.

So, as the eps doesn't (and shouldn't) have page size information, if one really wants the drawing to have the size of the canvas, the bounding box should be set to the size of the canvas.