Major update of CUPS is out
Standard UNIX printing system called CUPS got a major update (v1.5.0) yesterday. There seem to be several major trends in development of this version, including better security and various PPD related improvements.
The security related changes are privacy control for jobs and subscriptions in the scheduler, return of GNU TLS and OpenSSL support when multithreading is enabled, and validation and revocation of SSL/TLS X.509 certificates. The scheduler alone got nearly a dozen more improvements, actually.
The PPD related changes are mostly support for cupsSingleFile, cupsIPPSupplies, cupsSNMPSupplies and cupsFilter2 keywords, as well as improvements in the PPD compiler which now checks for overlapping filenames.
There are also some changes regarding filters. The PDF filter now supports new Ghostscript's ps2write device and a new feature by Poppler that allows preserving page size when user doesn't supply desired media size. Apart from that PWG raster filter has been added and HP-GL/2 filter has been removed.
Another interesting change is support for DeviceN that has been ported from an earlier stable v1.4.5. You can read full list of changes here.
As usual you can either install CUPS from source code or just wait till your Linux distribution picks it. Reportedly the new version is also part of recent Mac OS X "Lion".