Ubuntu, once king of the desktop Linux distributions, has slid into fourth place according to data made available by DistroWatch. On the flipside, the Mint distribution has enjoyed tremendous growth in popularity.
Taking the stats for the last 30 days and comparing them to the averages for 2010 show that Ubuntu's popularity is down 47.2%, while Mint is up a whopping 105%. The following chart shows how Mint's popularity has increased over the past 12 months:
Secondly, Ubuntu's decline started a long time ago. It's popularity has been in decline since 2005. Unity can't have been influencing this back then because it wasn't even a twinkle in the eye of the open source developers. While the popularity of Dedian, Fedora and openSUSE have all remained pretty constant (excluding openSUSE's initial rise to popularity after it's release in December of 2006), Mint has been on the increase and Ubuntu has been on a steady decline.
My explanation for Mint's rise and Ubuntu's decline isn't exciting but i think it's closer to the truth than the whole Unity business. Ubuntu got too popular and it tied to become all things to all Linux users. I've used both Ubuntu and Mint, and to me the Mint distro seems better suited to Linux fans (you know, the people who have been using Linux for years). Canonical Ubuntu have tried too hard over the years to make Ubuntu mainstream and appeal to the masses, and by going down this road have alienated its hardcore users. And now it's paying the price.
Try to please everyone, and pretty soon you please no one.
I won't be surprised when I find out that Ubuntu slid into fifth place ... prepare yourself, this is likely to happen in the next couple of months.