I think Palpatine won. Just because of how he is so good at manipulating things, I can't see him losing like that. And plus, he beat Yoda, who's more powerful than Windu.
One of my pet peeves is when people say, "Windu was more powerful than Yoda because he could beat Sidious." No, sorry, but in my book, you're wrong. I like to think that that's the obvious, basic, half-a** Star Wars fan response, but the real fans can delve deeper into the subtleties of it.
Peace is a lie, there is only passion.
Through passion, I gain strength.
Through strength, I gain power.
Through power, I gain victory.
Through victory, my chains are broken.
The Force shall free me.
-The Code of the Sith
In mourning . . .