Internet Explorer 8 RC1 has just been released. You can download it here.
Downloading/Installing
At a miniature 16.2mb IE8 RC1 took me 30 seconds to download and it took in 9 minutes + 1 restart to get to my first web page.
It also imported my FireFox feeds and bookmarks, which was useful.
Extensions
I couldn’t check what add-ons where available as the IE add-ons website was down (see screenshot). However, IE did open a nice tab showing some “accelerators” I could use (I think they are like google gears, but MS style).
Speed
Overall, IE8 seems faster than IE7 however compared to Opera, Firefox and Safari it’s just does not feel as snappy. However in most speed test done by professionals it’s a marginal difference, if you enjoy statistics take a look here.
Backward Compatibility
A really neat feature of IE8 is a built in “compatibility button”, which essentially means if a website is not working correctly in IE8 you can run it as if it was IE7.
Rendering
I love how it renders my pages, IE8 seems to render exactly the same as FF3.
There still seems to be some different padding/margin differences, but maybe something to look forward to in IE9?
Overall
I’m a firefox fanboy at ther end of the day, so i will not be moving to IE8. However, I will have it installed and I may use it from time to time 
Internet Explorer 8 seems to be the best browser for me. I can open more than 20 windows simultaneously without crashing. IE7 and IE6 is unstable that if you open more than windows at a time it just freezes or causes the blue screen.
IE8 is not a bad browser (like you said, it’s far better then IE6 and IE7), though I find it’s a good idea to keep an open mind with browsers.
Personally like Firefox, Opera & Chrome, but they are all not quite perfect.