Among the changes are CSS 2.1 support, CSS certification, HTML 5 support, new developer tools, activities and WebSlices.

One of the more heavily touted features of IE8 is passing the Acid2 test, and here it is finally in a version of Internet Explorer, on the default rendering mode no less.

Just because it can pass the Acid2 test doesn't mean that it can pass the Acid3 test. Although no other browser can yet lay claim to that either.

Rendering issues are to be expected with a new version of any Web browser that adheres to standards its predecessor did not.

Take for instance the video portion of the Builder AU homepage in IE7.

Here is the same section of the Builder AU homepage in IE8. The good news is that this was the only portion of the page that appeared to render incorrectly.

This is the lovely greeting that you receive when opening a new tab. Thank you IE, I had no idea what that Ctrl+T keystroke was going to do.

One of IE's unexpected quirks is the highlighting of the domain name that you are visiting. No doubt intended to prevent phishing -- no idea how successful this will be if a phishing site is properly cloned.

Activities are a new way to extend the functionality of IE8 -- there is already a selection of activities to choose from.

Add an activity follows the same process as a plugin, without the need for a restart.

Right clicking on a link with the Facebook sharing activity installed allows for sharing of links on Facebook, what did you expect it to do?

One of the more interesting features of IE8 in the big "Emulate IE7" button. This will set IE8 to render identically to IE7, however it does need a restart. I am not aware as to why it needs to restart when the next page shows how to change the render mode on the fly.

The new developer tools allows for quick changing of the rendering mode without restarting, as well as having the addition of an IE5 mode.

The developer tools also allow for inspection of the HTML code to deduce which styles are affecting what components.