With Apple controlling the development of CUPS open-source printing system, in recent years the major CUPS releases have immediately followed OS X releases. As a result, it shouldn't be much of a surprise that now with the official availability of OS X 10.9 "Mavericks", there is a new major CUPS release. CUPS 1.7.0 is the new version and it adds "polishing" to the multi-platform print server.
CUPS 1.7.0 isn't too incredibly exciting but it does introduce new useful functionality like better IPP Everywhere support, automatic support for data compression, and a new "ippfind" utility.
The new ippfind command with CUPS 1.7.0 is used for finding printers supporting IPP, the Internet Printing Protocol. The ippfind utility supports both IPv4 and IPv6 and supports various expressions for finding and narrowing down the range of printers reported.
The IPP Everywhere is for printing without printer drivers or applications and is a PWG standard aimed for both computers and mobile devices. "The goal is to make printing as simple as connecting a keyboard or mouse."
While a complete release overview is hard to come by, there is additional information on the new CUPS 1.7.0 release at CUPS.org