I also recommend the work done in the UK by Simon Tanner on measuring the impact of digitization projects and programs.  There are two publications, one very recent and information about them can be gotten to from Simon's blog:

Kari Smith
Digital Archivist
MIT Libraries, Institute Archives and Special Collections

-----Original Message-----
From: Code for Libraries [mailto:[log in to unmask]] On Behalf Of Kyle Banerjee
Sent: Monday, December 17, 2012 4:21 PM
To: [log in to unmask]
Subject: [CODE4LIB] Metrics for measuring digital library production

Howdy all,

Just wondering who might be willing to share what kind of stats they produce to justify their continued existence? Of course we do the normal (web activity, items and metadata records created, stuff scanned, etc), but I'm trying to wrap my mind around ways to describe work where there's not a built in assumption that more is better.

For example, how might work curating a collection or preparing for a migration to a TDB platform be described? Thanks,