Last April I chose between Penn (CAS) and Princeton (among other schools). Ultimately, given my area of interest, I knew Penn would offer me more opportunities, and it has- I'm beginning my M.A. next fall, as a sophomore.
Although I am not in M&T, I know that it is a highly specialized program and that the students are usually snatched up by top employers, which might be an advantage for you given the current state of the economy. I personally know two people who have turned down Harvard for M&T, and they don't seem to have any regrets.
The atmospheres of Penn and Princeton also factored into my decision: Penn is a very friendly, welcoming place, where we enjoy both a tight knit community and the resources of the city. And although all students work hard, Penn is a blast.
If as you prepare to embark on your college career, you are hoping to make these next years the best ones of years of your life, I can guarantee you that Penn will not disappoint you.
I hope this has helped.
Best of luck with the rest of your senior year!