well, firefox is currently using 61M of memory for me, but I also have 11 tabs open in it. So that's like having 11 IE's open.
Why FF over IE?
1) not based on vb script, so there are not secruity issues weekly
2) no popups! Mozilla long ago built in an anti pop-up feature that MS is just now getting around to. If I were a betting man, I'd say MS didn't want a pop-up blocker because it costs some of their customers money to do so. But it's pressure from the consumer that is driving this one, not trying to make the best browser
3) Tab browsing. now this is personal, but I use a LOT of browser windows. And with FF I typically have 8-11 tabs going every day. This means I don't have to constantly go back to pages. I do have to do reloads of course, but for instance, I have one tab always here for a quick reminder to read the posts
4) Session Saver. This is a plugin that unfortunately doesn't seem to be easy to find now. But the one i have from 4 or so versions of FF back still works. SS remembers every tab and what page it was on, and was those pages content was. So when the browser crashes or I shut down for the day, when I restart I always (except a couple cases where I mess up) have all my tabs just as I had them last. In the few cases I mess up, I just ask SS to restore my default tabs, and it recovers almost what I messed up. To me, this one is the best feature, having used it for almost a year now.
5) No Virus's. Combining Firefox with ThunderBird, Mozilla.org's stand alone email, forget about viruses. Almost all worms written today are VB script because it is so easy to get IE and Outlook to run those. FF and TB are not using VB so are never succeptable to the worms. Now regular viruses, sure, if you run the exe file they are in you're dead meat, but "you" have to know better.
6) Anti spam. TB also includes a built in spam blocker that learns, and I must say is doing a great job as well, except with Russian spam
It can't seem to grasp that anything in Russian is spam. haha
The big negative is FF does not always display a page correctly, as IE only sites do exist and can sometimes be a nuisance. but I'll live with that for all the extras. There is a plugin I have, that if I need to view a link in IE, all i have to do is right click, and choose View Link in IE. So that's a nice extra.
There are all kinds of fantactic little extensions for FF, and it's just a much safer browser to use, and more stable even as the 1.0 Preview Release just comes out. I have not regretted the change to FF/TB at any point.
I would say also, Mozilla also have a Mozilla 1.7/1.8 browser, that is what Netscape bases their all-in-one browser/email client off of. While it's mostly the same, I do not like it as much as FF/TB. Mostly because if Mozilla crashes, both the browser and email go. With FF/TB, when I do crash FF, it doesn't affect email which I just happen to like. It doesn't really matter I guess, as it's not like after restarting the program I wouldn't have email back, but I just like it.