We felt that with such fine control (now) over how and what does the launching, it would be a nice addition to extend that notion to perspective settings. For example, consider you have two profilers that both launch a Java application with profile options. Traditionally this would have led to perspective switching based on which-ever launch delegate was chosen in the end, leaving the user no control over what would be switched to based on what did the launching.
Now however, the user can select down to the launch delegate level to specify launch perspective settings. Changes to these setting can be applied on the Perspective preference page as before, with the only notable change being to the launchers tree (see screen shot).
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This new hotness is available in builds >= Jan 9 2006