It really feels like a truly high-end phone in the way that even the previous Nexus 4 didnt, and Google has clearly spent a lot of time perfecting not just how it works, but crucially how it feels. Theres a new "silk" backing which is a slightly sticky plastic, and makes the phone feel secure.
The touchscreen, buttons and casing are all a significant improvement, but at 130g, its the weight loss that makes the Nexus 5 a real revelation.
Switch it on, and KitKat takes over.
http://www.pocket-lint.com/news/124788-hands-on-nexus-5-review