When Google Nexus 4 was launched last year, it was available in only black color. The white one was launched later in May.
Recently we saw a leaked official image of Nexus 5 listed in Playstore. But that was Black. Now this leaked render shows a Nexus 5 in pure white. We are not sure about its authenticity but we may not have to wait long as Google is rumored to announce Nexus 5 along with Android 4.4 KitKat on October 28th.