Heat Dissipation an Issue with iPhone 3G?

[Khryz]

I just bought an iPhone 3G on Sunday and I bought it with a leather protectice case. I've been using it all day plugged into my work computer with a USB listening to music and browsing my apps and I notice it is a little hot.

Is heat dissipation an issue on these phones with cases on? Or is it normal for it to heat up slightly when using all day? It's not burning hot, but It's just a question I had.

 

[kornyboy]

Wirelessly posted (iPhone: Mozilla/5.0 (iPhone; U; CPU iPhone OS 2_1 like Mac OS X; en-us) AppleWebKit/525.18.1 (KHTML, like Gecko) Version/3.1.1 Mobile/5F136 Safari/525.20)

I think this is normal. I've had mine since the release and when I'm using it a lot I have noticed it getting a little warm to the touch. I've tried leaving it out of its case but that didn't do any good. I've never noticed it getting so hot that I would be concerned so I have chalked it up to normal use.