Although I totally love Firefox, I find that a combination of Firefox for AJAX heavy pages, along with Opera works even better.

I have Firefox and Opera on the same desktop, with Firefox in the 0 0 area and Opera just below it in the 0 1 area, so I can switch between the two with a simple CTRL-UpArrow and CTRL-DownArrow in Enlightenment.

With Opera, I take advantage of it's great handling of multiple tabs. Firefox is great with tabs, but starts taking up a lot of memory when you have 30 or so open tabs, like I do right now in my Opera session. Opera has some really wonderful features and works great completely from the keyboard, with probably better thought out shortcuts than Firefox.

So, I think, use both at the same time, they both have their benefits, and in Linux, they work side-by-side really well.

Here's some Opera links for you:

10 features you'll only find in Opera
Opera Tips and Tricks
Use Opera to do a slideshow