As an Xfce newbie I hadn't appreciated how cool the Launcher panel applet is until today, when I tweaked my desktop yet again to gain more window space.
Windows now occupy 1225x800 of my 1280x800 laptop display. At the top left of the display is a 48 px-wide, freely movable panel with the very nice Date/Time applet, notification area, log out and just 2 more icons. The vertical space below the panel (about 480 px high) is empty and available for changing workspaces by scrolling with the mouse (my preferred switching method).
The 2 extra icons are Launchers with 8 apps + 1 script on one and 11 files on the other. These act a lot like drawers in the Gnome panel: they open and close with a left click and have an arrow on them to show that they don't just launch one item. While the Gnome drawer applet would shoot out a new panel towards the right in this situation, populated with icons showing text on mouseover, the multi-Launchers shoot out a drop-down menu with little icons next to the text entry from the 'Name' spot in the Launcher dialog box. There are options for the position of the indicator arrow, and the 'Inside Button' option makes for a much neater icon than the big, ugly arrow in the left-vertical Gnome 2.28 panel drawer of the same pixel size.
After using the new multi-Launchers for a few hours I'm finding them much easier to use in a left-vertical panel than Gnome drawers. It's great to be able to easily tweak the positions of items in the drop-down menu, too, although it took a little while to work out
(a) top-to-bottom in the menu is bottom-to-top in the Launcher dialog box, and
(b) the Launcher icon itself can either be the top-most item in the dialog box, or a dummy placed at the top of the list with no command. In either case all that happens when you click on a multi-Launcher is that the menu appears.