Flashing IM tabs and changing shape of orange outline is overkill.

Flashing IM tabs and changing the shape of the orange outline to include the flashing tab is overkill.

I apparently don't consider the arrival of an incoming IM to have the same degree of urgency that the Linden staff member that asked the interface designer to make it so busy and flashy does.

The blinking IM window is often much more attention grabbing than the combined efforts of the builders, landscapers, avatar makers, etc. in the virtual world view.

A modest, non-blinking user selectable change in color and intensity of the tab would suffice for me.