Obviously it cannot be faster than a local DNS cache/server (for the RTT). What can be significantly faster is forwarding queries to Google Public DNS instead of your ISP. At least in my experience, ISPs often have slow and overloaded servers which are not well maintained. Recursively resolving completely on your own is often even slower than either of those two choices.

ISPs often also have abusive DNSes that redirect unresolved domains to ad-ridden landing pages, which is why I switched.

I have been running unbound for a month, and there is no noticeable difference in resolving time. This article provides a good read: http://linuxmafia.com/~rick/googledns.html

45ms beats the hell out of the hundreds, or thousands, that crappy Irish ISPs deliver from their own 'local' name servers. When they're working at all.