See here: http://www.w3schools.com/browsers/browsers_stats.asp http://www.w3schools.com/browsers/browsers_stats.asp What you can take from this is while being

See here: http://www.w3schools.com/browsers/browsers_stats.asp http://www.w3schools.com/browsers/browsers_stats.asp What you can take from this is while being IE compatible only will give you about 58% of users, you can see that FF is growing steadily and will probably catch up someday in the not too distant future. It also depends on what kind of web app this is. If it's something for younger people, or people more technology inclined, the FF visits may be a lot higher than the graph suggests.