Apple doesn't typically break out sales figures for specific iPod models, but I suppose the 100 million mark is something special. Hot on the heels of introducing a revamped iPod touch, Apple told Jim Dalrymple of The Loop that the company has now sold over 100 million iPod touch units.
Since first launching in September 2007, the iPod touch quickly became Apple's most popular iPod model, often accounting for more than 50 percent of quarterly iPod sales. In a world where MP3 players are dying a slow death thanks to the smartphone, the iPod touch has proven to be a resilient member of Apple's product lineup.
As a final point of interest, it took the iPad just two and a half years to reach the 100 million mark.