MarvinH - 8:43 pm on Jun 21, 2011 (gmt 0)
Why use FF when there's Iron!
For me it's because of a few plug-ins I use that are available for FF, and likely not available for Iron (I admit, I haven't checked).
But I'm not updating my FF 4.x unless forced to. A new version usually breaks a functionality of some plug-in, and I have to spend a while searching for a solution. I'll wait a little for FF5 :-)