Hmm, does seem a little high.
Before I upgraded the cooling, my 8600GTS used to be up at around 75C when gaming which for me was waayy to high. The 8 series and 9 series cards don't have very good cooling in my opinion and should always be upgraded with third party cooling.
I bought a Zalman cooler for my 8600GTS and it dropped load temps by 25C which is a HUGE drop. I now have two of these cards in SLI both using the Zalman cooler and both staying between 36C and 50C.
The games you posted are quite graphical games, so your GPU will be working hard and getting hot when running them. I would look into getting some extra cooling for saying the Zalmans I use were only like £20 a pop.
Alternatively, download yourself a copy of RivaTuner.
RT will let you set your fan to 100% and it will keep it that way, maybe helping with your temps under load?
Hope this helps mate.