How are we doing in terms of productivity? That's a tougher question. But as a first cut at that, lets look at the rate of package repository growth since Fedora 7.
Fedora 7 released May 31st 2007
has 5115 maintained source packages (this includes packages added post-release)
Fedora 9 released May 13th, 2008
has 7450 maintained source packages (this includes packages added post-release)
Fedora devel as of Aug 6th,2009
has 8639 source packages
That 12 month span between Fedora releases saw a growth of 2235 packages (not including packages added post F-7 release that were common to both) for and average of 186 packages a month.
The 27 month span since F-7 release saw a growth of 3524 packages for an average of 130 a month
The 15 month span since F-9 release saw a growth of 3524 packages for an average of 79 a month
These are actually an undercount on repository growth because of the way we doing things. Branches grow over time after release date, and new packages would be included in both F-7 and F-9 during the release overlap associated with the F-9 testing period. So with that caveat in mind..what does this mean?
It definitely looks like we are slowing down in our rate of repository growth. But my previous analysis looks like our maintainer pool isn't slowing down like that yet. I would need to repeat this analysis including F-8 and F-10 to confirm that and see if they fall on the same trend. This may point to a concept of an effective carrying capacity for the size of a repository, It's not really surprising for a number of reasons.
For completeness the same sort of analysis can be done for Debian and Ubuntu making use of the scripts found here:
Debian has long release cycles so its harder to test the carrying capacity trend with Debian data, but it is instructive as a realtive comparison of a mature project. If there is an inherent carrying capacity effect has Debian as a more mature project reached it? Maybe they have.
Number of source packages in etch main: 10221
Etch release date: April, 2007
Number of source packages in lenny main: 12176
Lenny release date: Feb, 2009
That 26 month span between releases saw a growth of 1955 packages in main for an average of just over 75 packages a month.
That average packages per month for Debian is similar to where Fedora is now in the last year. That's interesting.