"Many" refers mostly to the Gameloft games. There are many other 3D games out there that the exynos can't run. I'd say "handful" instead.
errr, nope, Gameloft has never done any "Tegra 2 only" games that I'm aware of, so all their games will probably be updated to support Exynos eventually.
I think "many" referred to the games which are supposed to run only on Tegra 2 devices like Samurai Revenge 2 HD, Pinball HD, or Guerilla Bob THD, but which work perfectly on Exynos once you use the appropriate drivers, proving that the "Tegra 2 optimised" is just marketting and a software lock.
Just wanted to make that clear, but actually I agree that most games will probably be optimised for Tegra 2 since it will be the most common platform. (Also Xperia play seems to have lots of games designed for it... I guess it's good news for those who are stuck on single core/Adreno 205 phones...)