How to describe - not hot enough to make it burn or untouchable, but hot enough to know it's a hell of a lot more than warm. My guess would be about 35-45C.
It gets hot at the top are only - browsing, using the Nokia Maps - stuff like that - for say 20 minutes.
If I hold the top area, my hand acts as a good enough heat sink to pull the temp down.
Hopefully other 920 owners will be aware that the 920 has had some overheating issues on *some* phone (I don't know the numbers).
How hot does your 920 run?
What's too hot?