I can really relate to it. Not counting the upcoming Sochi games, the first (and the only) time Russia has hosted the Olympics was in 1980. Actually, it wasn't even Russia at that time - it was the Soviet Union. I wasn't there to witness the grandiosity, but even decades afterward my parents would talk about how mobilized and united the country felt during the games and how exhilarating it was to welcome all these visitors to our land, which at that time was still very much behind the iron curtain. And sure enough my family owned several versions of "Misha the Bear" - the official mascot of the 1980 games.
I think the best time to visit Beijing Olympic Park is after dark because brightly lit up buildings look very dramatic against the night sky.