XFCE requires the use of 2 panels. It would nice if we could customize it like gnome and kde can be customized, with one panel holding the "Start button", show desktop button + the taskbar. Reproducible: Always Steps to Reproduce: 1. 2. 3.
You can already do this. See the xfce4-taskbar plugin at http://xfce-goodies.berlios.de/. There's no need to run xftaskbar4 if you don't want it, and everything that goes in the taskbar can fit into the panel now.