Now that the HAT has been deprecated in BizTalk Server 2009, the BizTalk Server 2009 Administration Console replaces some of the HAT’s previous functionality.
To retrieve the Most recent 100 service instances use the query shown in the sceen shot below (Search for Tracked Service Instances).

Most Recent 100 Instances
The HAT is still used to to display the Message Flow and Orchestration Debugger when right clicking on a service instance in the above screen shot.
You can still bring up the HAT at the command line as shown below(replace the MgmtSvr and MgmtDb with the appropriate values).
“C:\Program Files\Microsoft BizTalk Server 2009\”BTSHatApp.exe btshat: MgmtSvr:CSI00SRV01 MgmtDb:BiztalkMgmtDb

Command Line
But only the File and Help menus appear. The Reporting, Queries and Tools menu do not appear. Apparently, you can only invoke these functions from the Admin Console.

HAT
Where did you get that HAT is depreciated?
Hi,
In computer software terminology deprecation is used to indicate that a feature may be removed in the future.
The HAT does not appear anymore in the Biztalk Server 2009 Menu.
Its functionality seems to be superseded by the Admin Console although the Admin console still uses some of the HAT functionality.
Richard Seroter blogged about the demise of HAT in Biztalk 2009 at
http://seroter.wordpress.com/2008/12/10/so-whats-actually-in-the-biztalk-2009-beta/
Kent Weare also blogged about the HAT no longer being available in Biztalk 2009 at
http://kentweare.blogspot.com/2009/01/biztalk-2009-beta-wheres-my-hat.html
I hope this helps
Harold