I’m a pretty regular user of both Firefox and IE on Vista. It helps to run both so I can test the results produced my meager CSS skills. I’ve noticed that there’s a few things I’d really like each browser to steal from the other.

Firefox please copy the fact that IE:

• creates new tabs to the right of the current tab you’re on. I’ll admit my evidence is anecdotal here but when I’m in the middle of browsing a page and want a new tab, it’s almost always something I really want close to what I’m currently browsing. IE totally got this right. I often have more than a dozen tabs on screen. Firefox will create the new tab all the way to the right often pushing my current tab offscreen. Going back and forth between the two sucks.
• has a button to the right of the rightmost tab to create a new tab. This is logical and helpful. Firefox could use this.
• handles text boxes properly. Text boxes may seem like simple entities to many folks but they are complicated entities with lots of user experience subtlety. For example, there are tons of small keyboard combinations that make navigating around a text box (with and without selecting) much easier. The arrow keys are the simplest example. But what happens when you want to select all the text prior to the cursor up to the point of the first paragraph break from the keyboard? You hold down shift-ctrl and choose the up arrow. This doesn’t work in Firefox. It’s super annoying especially if you’re writing/editing blog posts.

IE please copy the fact that Firefox:

• restores your session when you start again. There’s so much opportunity to do a better job here. Great place to leapfrog.
• supports Google Sync. OK. I admit it, it’s not a FF feature per se. But not only will it roam your session state, but your faves to boot.
• has Firebug for debugging your CSS. Firebug kicks ass. Clone it.

I’m sure I’ll find more down the road but that’s it for now.