How Highway Signs are Getting Clearer (finally!) August 27, 2007 | Posted in One-link-ers | 3 replies The Road to Clarity – New York Times
Obviously it’s just me, but the only difference I see between those two demo signs is the little serif on the “l”s.
There’s a lot less old green goop on the new sign ;)
Seriously, though, if you want a good review of what the differences are, check out the slide show associated with the article.