Middle class to me is anyone not receiving food stamps or welfare and actually has a decent job (and worries about getting laid off),a house, rented or otherwise, a couple of cars and an occasional vacation and not necessarily any money in the bank for emergencies, especially in the last 3 years or so.
Upper class is what it always has been, anyone who has a really nice house or mcmansion(regardless of whether certain political groups think it's too big for them or not, it's their money). Probably owns a business of some sort and is quite comfortable financially. Vacations don't mean anything necessarily, because there are upper class people out there that don't take vacations and they are probably able to send their kids to college without having to fill out student loan applications.
Just my opinion.