I do some tech support at work for three people running MBA 13" with thunderbolt and had to replace the case on one as it cracked from overheating. In this case the use was only office applications and some light image editing in photoshop. So I purchased a few cooling stands. One with a fan and the others were just metal stands. This seemed to fix everything. The MBA with the better cooling stand is used for some pretty heavy video editing in the adobe ultimate suite. I personally think that even though the unit runs cool enough, it's putting some heavy wear/tear on the unit. So my advice to you would be to avoid stressing the unit that much if it's your work machine but if you can't resist, get yourself a good cooling stand with some fans.
Jon P D
Unfortunately I have not tried to play WoW on this MBA yet, it is realy a pain for my ears to listen to the fan noise from such a thin machine. And I also use iStat menus and temperatures like 98-100 C excite me even more. But as soon as I decide to game a bit - I'll post here ))
Thank you very much for a professional advice ! This information is very usefull, because EVERYTIME I rise the question of high temperatures everyone sais "its ok dont worry, its mac, its Apple, so everything should be ok etc". And finaly I do hear about overheat issues. As for me, I ALWAYS use Just-Mobile Cooling Bar if I use the integrated monitor, otherwise I use Twelve South stand - when connected to an external display (both of these cooling pads provide passive cooling).
So if you do not recommend stressing a work machine I will not do it for sure. I'll look for some other gaming solution...maybe iMac... or replace MBA with new thin MBP . . . Or maybe Apple will intergrate GPU in the upcoming thunderbolt display lol ))))
Otherwise it doesnt make much sence.