Does anybody else's nexus 7 2103 run really hot when doing a video chat on Google hangouts? I find it hard to believe google's own hardware cannot handle its software any better!
I don't have a Nexus 7 but you have to consider that Hangouts is using both the internet and screen constantly. Both running create heat and there is nothing software can do to prevent this other than more efficiency. However, a phone is a small device as is a 7" tablet such as the N7 so you can't expect much more.
Anything that taxes the system will cause it to run hot. As long as it does not damage the device (and I have not heard of it doing so) it is considered acceptable. it's not just Google's own devices.
My Galaxy S3 and Note 2 both ran hot when video calling on hangouts. It doesn't get that hot when using Skype though. I still haven't used either on my Nexus 7, but I'm thinking there might be something going on with Hangouts in particular.