If you're on WordPress and value your users privacy, do not use Google Analytics.
Sure, webmasters get to take advantage of big brothers' trove of fingerprinted browsers and fancy metrics, but you're also diming out your users to Google and feeding a beast that's already obese.
Google benefits most when you put Google Analytics on your site. Now they can track your users. Webmasters getting analytics out of the deal is the only way Google can sign you up to spy on your traffic.
That's why I use the 100% self-hosted WPStatistics plugin on my WordPress.org blog. And it's considerably faster than Google analytics too, because you don't have to make your clients do an extra DNS query and download external tracking scripts from 3rd party (Google) servers.