At the time, I assumed it was a perfect clone of DOS’s Code Page 437, the one used by most western monitors. However, just recently, Adam Moore just published two different iterations on the font called More Perfect DOS VGA 437 and Less Perfect DOS VGA 437. From his page:
Zeh Fernando made Perfect DOS VGA 437 back in 2003, and it is almost the best TrueType VGA font out there. To my eye it looks a bit too spaced-out horizontally; this is for a couple of reasons. I made the following alterations to his font to address them.
First, while his font is done on a proper 9×16 pixel matrix (VGA characters are stored as 8×16 matrices in ROM, but the adapter displays them in a padded 9×16 cell), none of the alphanumeric glyphs are more than 7 pixels wide, which isn’t as it should be. For More Perfect DOS VGA I fixed the capitals T and Z, both cases of M, V, X, and W, the zero, the ligatured AE, and a few other glyphs to better match IBM’s VGA ROM font. The result of this is that some glyphs lie a little closer to one another, which makes text look a little less spread-out.
While I will still maintain that I did a perfect copy of the character as I saw them on my monitor, it’s likely that his glyphs are indeed more correct – after all, I lived in Brazil, and it’s high likely that the control cards used by the monitors I had access to were not exactly original IBM (my whole early computing life was spent on clones of more successful brands, after all). So, if you’re looking for a more kosher duplicate of the DOS fonts seen on the original IBM PC terminal, his are what you’re looking for.
Update (January 19th, 2016): also be sure to check The Ultimate Oldschool PC Font Pack, which includes remakes of nothing less than 81 different font sets (including the VGA font). Thanks rötorhead for the link.