I guess I'll advertise my apt
there are currently 6 vet students living here.
http://www.leftbankapts.com/
Only cats allowed, one time fee. Rent between $1700-$2500. Moving in with a roommate or your significant other is best because then you pay $1000 or less per person, which actually is a good deal (if you are used to city prices). Washer/dryer in unit.Gym, Roof deck, courtyard, library for studying and conference rooms for studying. Secured garage and outdoor parking pay per month.
This apt complex is in center city and we have a friend who lives there, this is by the museum like SOV was talking about.
http://www.parktowneapthomes.com/
They are also really nice, I have no idea about price or anything else though. They have a cat, I'm not sure about dogs.
Some others that I don't know about but I see all time:
http://www.2400chestnut.com/
http://www.riverloftapartments.com/ (I think dogs are allowed here)
Also, I know you all will probably use ratemyapartment to see reviews. What I have found is that Philly reviews are totally skewed. I'm not sure if it has to do with people who aren't from the city and then move here so they aren't used to things. I know I saw a could bad reviews for my apt complex but I've been here for 2 yrs and love it. And compared to the problems I had in DC, this is like heaven haha So I'd try to get opinions from inside sources if you can find them.