Akzidenz-Grotesk is an interesting font choice. Its kerning makes it less readable than Helvetica but its glyphs are beautifully designed and very distinctive. It's an iconic font, but at the end of the day I think Helvetica surpasses it in terms of practicality.
Still wonder how MTA would look like with this design.
It indeed is beautiful piece of "UX" design. And as someone who live in NYC for quite a while: to only thing you can count on in the NYC subway system are the directions.
http://thestandardsmanual.com/images/large/nycta_gsm_068.jpg
Gives me goosebumps.
Whitespace. Love it. Embrace it.