I was loving Bisping when he said 'like that' after the knee to the head at the end of the round. If some prick started ripping the piss out of me out of nowhere with all his mates and saying my girl was a koala with clamydia I would seriously want to hurt that dude. Rivera deserved the knee to the head for being such a classless clown before the fight. The whole charade worked badly against him and he deserved a beat down. The whole apologise thing was a bit much after the fight but with all that adrenaline pumping he's not exactly thinking clearly.
You can't condone that behavior though, it was foolish.
Ok he was fired up, but that knee was a flagrant violation of the rules and was stupid to the extent it could have cost him the fight (plus it was so unneeded as he was clearly too good for Rivera without having do resort to such tactics)
After the fight acting the way he did just made him look like a clown. He had won the fight, with ease, proved his point and shut Rivera's mouth with his fists.
He would have been a much bigger man if he had just shook the guys hand and even quietly said "that's what you get for talking about my family"
It's not the biggest deal in the world though, at the end of the day its a fight. Ok he makes himself look a bit classless and it reflect poorly on the sport somewhat BUT those types of things get people talking and generate more interest. Like it or not, the sport needs the odd controversy or contentious incident to keep its profile growing.
If everyone conducted themselves like GSP it would be a very admirable but also very boring sport (because there would be no reason to hate any fighter ever and how would you really chose who you want to win aside from National alligance?)