I tell the students in my software engineering classes that the absolute value of code coverage in testing isn't as important as the trend: if you're testing a smaller percentage of your software as time goes by, you're headed for trouble. The same is true of site stats: I don't care much about the absolute number of visitors, but if the curve is down and to the right, it's time to give the site a polish, or retire it.
Which brings us to this year's stats for Software Carpentry:
Looking at visits (upper right), things aren't too bad. Looking at pages, files, and hits (on the left), it's clear the web is losing interest. And looking at the total downloads (bottom right), I'm just confused: we didn't do any major surgery on the site, or retire any heavyweight content, so I don't understand why traffic weight would be cut by two thirds.
So that's another of my New Year's resolutions for 2009 that will be a repeat of one made in 2008: give the site a makeover. If you have 50-100 hours of quality time to donate to help, please let me know...