Remember the time when many doubted Firefox would reach 10% market share? It's been some time now that Firefox reached and surpassed this level, and the evolution of the project makes it look to the next step: improve rentention rates (this is the percentage of people downloading Firefox actually continuing to use it). This retention rate is suprising low, at about 25%, and a new plan is in the works to improve this retention rate.
I was actually surprised at this low retention rate. I thought people downloading Firefox were already convinced that it was needed to switch, which would have given a higher retention rate than 25%(only 1 in 4!).
I haven't seen documentation about their methodology to get this 25% figure. It would be an interesting read.