Squealing fan belt covered under warranty by TSB. The squeal has since come back, but the dealer claims that a new TSB has been issued dealing with the power steering bracket (aka the culprit)
Fog lights crack - covered under warranty, but DO NOT wash them when they are hot. Also, ensure that there is no snow packed in them when you turn them on!!
Paint chips - Pearlized White chips extremely easily.
Interior plastic - scratches easily.
Break click when reversing - Fixed under warranty (TSB)
Electrical gremlin - thermometer/time display sometimes fails to light up when headlights are turned on.
Thus far, the Aerio is a good vehicle. My wife likes it and it handles snow well. The gas mileage is decent and the power, while not outstanding, is adequate. The car will not shift into high gear until it warms up and the engine temp light goes out. This can be annoying as I am sometimes already to the freeway and it is still not ready.
Visibility is a concern as the center beam is located in a poor position for an average sized male. Shoulder checking is made difficult and I have banged my head off the top of the window frame on several ocasions (5'10")
The heater is decent and provides lots of BTUs.
The Aerio is a decently priced AWD alternative to Subaru, but the overall finishing is somewhat concerning.