Grand Theft Auto fansite GTAGaming have added a preview of GTA IV's subway network to their website. Full descriptions of all stations, nearby landmarks and passengers are included, along with screenshots of many.
"The next stop is Feldspar and it's from here that you'll gain the easiest access to the city's most notable landmark, the Statue of Happiness. Presented to the USA by France in 1886, it marks 100 years free from British food and spelling. Unfortunately for many seasick tourists, the Statue stands alone on Happiness Island, which can only be accessed by boat. Tickets are sold not far from Feldspar, so if it's a warm day and you're not getting off here, you'd be well advised to stretch out on your seat to prevent it from being taken by someone who'll probably drip their ice cream on your legs."