I blogged about IE8, Tab Groups and Task Manager earlier and mentioned about many iexplore.exe processes in the Task Manager.
It turns out to be that there is nothing wrong with IE8. Its the new feature called Loosely-Coupled Internet Explorer (LCIE) which is introduced in IE8. From the IE8 web site:
Loosely-coupled Internet Explorer (LCIE) is an architectural effort to improve the browser by separating its components and loosening their interdependence: most notably, it is an attempt to isolate the Internet Explorer frame and its tabs into separate processes. In Internet Explorer 8, this isolation will bring about improved performance and scalability, as well as more potent methods to recover from problems like disk or system failure.
So with IE8, the UI Frame and the Tabs function as separate processes, and thus the more tabs you open, the more iexplore.exe processes you might see in the Task Manager. And, this number is controlled by power of your computer. The more power, the more tabs you open, the more iexplore.exe processes will be created. And also they perform tasks asynchronously.
Here is how it looks like:
And thus when we open IE8, we get two process running, one for the UI Frame and another for the tab
This is indeed a good feature and also separating processes might also help a lot in the event of any failure
More information on LCIE here