:-) That one and the white are both skins! You get both. There's even a little installer script to switch back and forth. The new bit is the FrogSnap window (no skin for it, it's just a little utility window... well, not yet anyway!)
Someone could fairly easily make their own skin too. I could see Mr. GlowIcons making a skin too. It's basically selecting the background, and using the size of the image-buttons to determine the layout. Change the buttons, change the MUI prefs, then copy the frog.prefs out of env:mui/ to somewhere else to put into the archive with the buttons.