The Nexus S of course is the new kid on the block and the only phone running Gingerbread Android 2.3. Both phones are high-end devices and neither will leave you lacking in the feature department. The main difference will be that the Nexus S comes with the pure Google experience no additional custom UI to love or hate it is meant to be customized to your liking. The HTC EVO 4G however does have a custom UI and the Sense experience is definitely considered one of the top two Manufacturer UIs along with the new Moto Blur. The video goes into the details of the phones does the Nexus S dominate or come out lack luster?
Check it out
http://www.youtube.com/watch?v=7Po6kucae74&hd=1