In my experience, it is slow only on very media heavy sites like Facebook, Youtube etc. That's not going to improve unless there are many more exit nodes and relays. But for most browsing its not painfully slow, although the slight delay is noticeable when compared to a non-Tor browser. However I guess the best way to fight public perception that Tor is a den of illegal activities, as well as foil timing attacks is for more of us to use it for regular browsing.