Doing an analysis on OpenOffice.org's applications is equally revealing. In Ubuntu's results, OpenOffice.org Writer is installed on almost every host measured by popularity-contest, while, on Debian, slightly more than half the hosts reporting have OpenOffice.org installed.
However, in both cases, the popularity of separate applications -- which can be installed separately -- is consistent. In each set of data, Writer, OpenOffice.org's word processor, is most likely to be installed and recently used. It is closely trailed by the Calc spreadsheet and the presentation program Impress.
In fourth place is Draw, and in fifth place the database Base. And, in the Ubuntu results, Base has about half the installations, and only about ten percent of recent uses of any of the other applications -- a result that may suggest that many desktop users continue to be intimidated by the idea of databases.
The popularity contest data also reveals how often equivalent programs are being used. For instance, on Debian, Evolution is the most commonly installed email reader, appearing on 50% of installations, but only a few percent have used it recently.
Meanwhile, 16% have KMail installed, and 15% have Icedove, Debian's non-branded version of Mozilla Thunderbird. You receive comparable results on Ubuntu, except that Evolution appears on 88% of installations and has a recently-used rate of about 5%.
These figures suggest that, although Evolution is installed with GNOME by default, it has been unable to obtain a high level of acceptance in its fragmented category. The same is true of KMail, despite the fact that most installations of KDE include it.
But perhaps the most interesting figures are those that compare FOSS packages with proprietary ones. Ubuntu installs the free nv driver for NVidia cards, but on over 86% of machines reporting, the proprietary NVidia driver is also installed. In much the same way, the free Radeon driver for ATI cards is installed on one-eighth of reporting Ubuntu machines, while just about as many machines use the proprietary fglrx driver.
But on Debian, the proprietary Nvidia driver has only one-fourteenth the installations of the free nv driver, and the proprietary fglrx driver one-eighth those of the free Radeon driver. Noticeably, too, although the Ubuntu statistics are roughly twelve times larger than the Debian ones, the number of installations of the free Intel video drivers on Debian is one-third that of the installations of the same driver on Ubuntu.
This sampling of possible inferences also seems to suggest that, while Ubuntu is based on Debian, the audiences for the two distributions are distinct.
In general, Debian users seem more eclectic in their use of software than Ubuntu users, and less likely to use an application simply because it is included by default. Debian users also seem more likely to be concerned to maintain a free installation than Ubuntu users -- a conclusion that is hardly surprising when you consider Debian's reputation for freedom, but is still interesting to see being supported by statistics.
To what extent last week's figures are typical is uncertain. Very likely, studying the figures over a longer period would produce different results. Possibly, too, those who participate in the Popularity Contests are not typical users of either Ubuntu or Debian.
For instance, the number of recent upgrades would undoubtedly depend on how recently the latest upgrade for a package was released, with upgrades peaking immediately after a release, and declining at the end of another release cycle.
Probably, too, any given set of figures includes some anomalies that would be evened out over time (which is one reason why I give approximate figures most of the time; citing the raw data would only give a false sense of precision).
It would be interesting to see how the results from Ubuntu and Debian compared to those of other major distributions -- and, conversely, to see Fedora's hardware-reporting Smolt ported to Ubuntu and Debian to give an even more fully rounded picture of user habits.
However, neither event is likely to happen in the immediate future. For now, Popularity Contest provides a rare view into the habits of two sets of free software users, confirming expectations in some cases, and also offering the occasional surprise.