I installed IE8 right away when it came out yesterday. As someone who requires only a pretty modest feature set, it didn't really make much of a difference to me. I can still surf the web, ya know?
The new feature I liked the most is the favorites bar where you can arrange your favorites horizontally below the address bar. That way you get rid of the side favorites menu, gaining more screen real estate in the process.
Otherwise I couldn't really tell much of a difference or put any of the other new features to any good use.
Still, I'm using Firefox 3.0x now (which I have always had installed in parallel). Not because IE8 sucks per se but because one very important (for me) IE add-on is not available for IE8 yet. I'm talking about
IE7Pro which had ad blocking and a Flash blocker and a few other useful features. I was mostly missing the ad/Flash blocker so I'm going to be using FF3 now until they come out with IE8Pro or maybe I'll stick with FF3 now... dunno.
...but across the board is slower than firefox...
From personal experience with both and as I said as someone who's not doing much fancy stuff on the web but just regular home usage (banking, sports, gaming, hardware, news, online shopping, business sites etc.) I can not confirm that. They seem about equal in performance and I have read some other reviews where real world testing has shown that they are basically tied for speed.
However, what is true is that FF3 is a lot faster in scenarios where
a lot of JavaScript is involved (which is not really that often the case in regular web usage). Seems like the JavaScript engine in FF is a lot more optimized as was also proven by specific synthetic benchmarks where the browsers had massive amounts of JS thrown at them.
But in day to day usage I think you'd be hard pressed to tell a difference unless you're one of those people who has the ability to switch to bullet time so you can slow the world down around you and get down to business with them milliseconds
.