More than 10% of net users are going online with the Firefox browser according to analysis firm One Stat.

In US it has higher shares of 14%.
Link

However there appears to be a consensus among technical blogs that Firefox usage is around 50% in technology users. I had posted before about this (see in links below).

The numbers are expected to grow.

What is unexpected is the gradual slowing down of the rate of growth. It appears Microsoft has played a wonderful move in announcing IE 7 which is responsible for curbing the mass exodus from Internet Explorer.