Taskbar? Hmmmpf... That would be weird... You would not have conversations in the taskbar so you would have to switch between them using... alt+tab?
Just18 some folks confuse taskbar with system tray as it's all on 1 panel ...
If Pidgin is permanently open then different conversations can be in the one window, but on different tabs.
If it is never minimised then there is no need for a Task Bar entry to be showing.
That is as I understand the o-p's use.
Notifications of new messages should still show from the System Tray icon, as well as indicated on the specific tabs.
Examining how I have used Pidgin since this thread started, I can say I do not use the Task Bar icon either, and have Pidgin open most of the time. I do not minimise it but instead close it and open it again from the System Tray icon.
It hasn't bothered me as I have the Task Bar separated on its own panel which auto-hides and there is no lack of space or crowding on that panel normally.
I guess the reason Gkrellm has a 'switch' for the Task Bar icon is because it is designed to run full time on the desktop and so it might not require a Task Bar icon -- it would not be minimised in the normal course of events.
I haven't found a 'switch' for Pidgin to dispense with the Task Bar icon ..... but I suppose it might be possible to do it by editing some config file .....