no, it is correct. gaming cpu hirarchy chart's cpu performances are based on stock performance of cpus.
most games is 2 cores, few use 4 cores. core i3's 2 cores turned out to be as strong if not stronger than overclocked phenom ii x4, x6, fx8xxx series cpus.
http://www.tomshardware.com/reviews/gaming-fx-pentium-apu-benchmark,3120.html
it also uses far less power than amd cpus (both stock and oc'ed).
there have been a few software updates since, skyrim isn't as cpu dependent as before.
if you use an entry level gfx card like radeon hd 6770 or 6850 with a core i3 vs an fx 4100, you won't notice any difference. but if you use a 7850, 7970 or a gtx 680.. the differences will be more apparent.
http://www.tomshardware.com/reviews/fx-4100-core-i3-2100-gaming-benchmark,3136.html
core i3 can handle higher end cards better than it's amd counterparts and some higher end amd cpus. it can do that while consuming less power.
core i3 however, will get outperformed in multithreaded apps like x264 video conversion, 3d rendering, file zipping/unzipping with 7zip etc by phenom ii x4, fx 6xxx/8xxx cpus. then again, core i3 isn't suitable for 3d rendering anyway.