Ever since we had our house insulated in the fall, we've had crazy condensation on the few windows that are original to the house (which is crazy old). We never had this happen before because the inside temperature was never so far off from the outside temperature... and there was always plenty of air flow (air blowing straight in from the outside, and vice versa) to prevent condensation from building up.Getting those windows replaced, or at least covered with some type of storm window is definitely on the top of the to-do list for 2011.
It's a long list already.