I'm don't always think too much about the performance of web browsers. As far as I'm concerned the bottle neck is normally the internet connection but Sam Allen has compared Safari, Firefox, Flock, Opera and Internet Explorer for memory usage.

Safari used the most amount of memory, an eye watering 636.9MB. The only time I've come close to that figure is when running a virtual PC. Having said that I did run Safari for a little while and it didn't seem to use that much memory. As I'll come on to say with Opera, there's no information of the actual browsing habits.

Firefox did the best with just 111MB of RAM used at the end of the browsing session. The key to what I imagine will be fairly large variances in experiences will be what add-ons are installed

It's good to see the improvement from Flock. As much as I liked this browser, I had to stop using one of the earlier versions because of a memory leak (an ever increasing memory load). Sounds like it's time to give it another go.

Internet Explorer performed about the same as Flock

Just for reference Opera is using around 166MB at the moment on my desktop compared to the 190MB quoted in the test results, and that's with 28 tabs open. Doesn't seem too bad compared to Sam's experiences but unfortunately there is no information about the number of tabs open at a time.

Thanks to Gervase Markham for the link