Just a quick blog about another feature of Loosely Coupled IE (LCIE)…
When using IE8, you may notice that a tab process does not exit right away when you close the Tab window or when IE navigates away from it (due to changing Mandatory Integrity Control (MIC) levels, for example). For performance reasons, an unused tab will live for 60 seconds before shutting down. There is, however, a registry key available to control how the unused tab process will wait before it is destroyed.
Registry key details:
HKCU\Software\Microsoft\Internet Explorer\Main - TabShutdownDelay
Setting this DWORD value key to 0 will force the tab process to be destroyed as soon as IE navigates away from it. The value is in milliseconds. Keep in mind that if you want 60 seconds, you need to put in 60000 as a decimal value, not a hex unless you do the math first.
Note: If all of IE windows are closed then all the iexplore.exe processes will exit immediately.
The IE Support Team