Thanks for your reply.
I have many different applications (some internally developed, some third-party, some OLTP, some DW), so in my case, it is not development vs QA vs Production, it is more application 1 on SqlWindows 1 and application2 on SqlWindow 2 (totally unrelated tables/objects). So instead of having multiple PL/SQL Develolper "instances", it would be nice to have different SqlWindows connected to differnent databases. Hey, that's why Mozilla "Tab" browsing model rules, as opposed to open-a-new-windows of IE.
I would like to hear from Allround Automation Support if this has been consider as an enhacement.