I posted in the past about the upgrade from Firefox 1.7 to 2.0. As I mentioned, the change was not dramatic and I only found minor changes.
Interestingly, I also just upgraded to IE7 from IE6. Wow, that is a big change. The UI is very different; they have hidden all of the previous icons in other locations. If you consider Firefox2 and evolutionary upgrade, then I would say that IE7 is an revolutionary. I am not referring to feature or function of IE7, but rather that the new version completely changes the UI. Currently I am mixed on it. IMO, you should not have to read a manual to use a browser, it should just work and be self explanatory. This has always been the way with Firefox, but unfortunately, the same cannot be said of IE. I find the UI confusing, and hate how they have hidden so many icons. I recently had to hunt to find the “reload” button. (It is the two arrows next to the address bar.)
I imagine that certain people might look the new look and feel, but I find it annoying. I also judge these things based on what my other (not a computer expert) would think. She would find the tiny icons on the right confusing and would not know what to do with them. I also find MS’s use of tabs to be somewhat confusing.
My current preference is Firefox 2.0. Yes, it was only an evolutionary step from 1.7, but that is good because you know what you are getting. IE7 too new and confusing and I do not have the time or energy to figure it out. I am going to stick with IE6 on my other machines.