Well, for legal reasons (antitrust with respect to integrating IE and Windows), SP3 ships with this disabled.
If you want it back, get the previous version of browseui.dll (it'll be in a service pack folder somewhere - anyway it's 999kb dated 23 Sept 2006) and copy it into c:\windows\system32, overwriting the file from SP3.
Reboot and the ability to get the address bar in the taskbar will be re-enabled.
And, before you install SP3, read all the release notes!
Regards
If you want it back, get the previous version of browseui.dll (it'll be in a service pack folder somewhere - anyway it's 999kb dated 23 Sept 2006) and copy it into c:\windows\system32, overwriting the file from SP3.
Reboot and the ability to get the address bar in the taskbar will be re-enabled.
And, before you install SP3, read all the release notes!
Regards