I didn't watch the whole thing, but my overall impressions are:
I think Biden did very well; he was aggressive and spoke well and didn't really let anything sneak past him; although I could have done with a little less joviality. Specific political positions aside, you have to give Joe Biden respect as a seasoned debater.
I think Paul Ryan did great; he had a couple of spots that I think he could have handled a bit better, but overall an impressive performance. the bit where he was asked for specifics and kept going back to pr-speak was painful, if only because it stood out against his otherwise excellent performance. He should have just said "I have 2 minutes; it's not nearly enough time to answer this. But I will make sure that the specifics are made available to you and the American people at our website by tomorrow morning."