There are lots of great places in Center City. A lot depends on how many people plan to go and what kind of drinks everyone would like (general pub stuff, specialty drinks, etc). There's a great thing on Wednesdays from 5-7 during the summer called Center City Sips, where tons of restaurants do a cheap appetizer, mixed drink, wine and beer menu. I know there's a website for it, but I don't know the address offhand. But it'll give you a good idea of what's around, other than basic pubs.