I know, it is still some time to go, but: For my first semester break in February 2012, I already have made plans and booked a flight.
It’s an enormously cheap offer by Austrian Airlines: Vienna – New York for less than 390 Euros!
I will stay in the US for 2 weeks, with short trips to Boston, Philadelphia and Washington. I already spent 4 days in New York some years ago, and I guess, I’ll have about one week this time :)
By the way, the offer by Austrian Airlines is only valid for the rest of today. There are also cheap flights to Toronto (around 450 Euros) and Washington (around 500 Euros).