I just noticed this change in the sound menu and I’ve very pleased so far with the progress!
The menu is beginning to take shape nicely, but don’t get too excite just yet. While the back, forward and pause/play buttons do indeed work, they don’t currently have any mouse animations. By this I mean that there is no visual change when you click them as you would see in a regular button. The pause button also doesn’t toggle back to the play button.
Eventually the menu will gain a few more features as are displayed in the following mockup.
After the song progress bar and time are inserted, there won’t be much more to look forward to usability-wise other than the playlist sub-menu’s. I’m sure there will be several tweaks and adjustments coming along after these features work their way in, but they seem to be piecing things together in a very orderly fashion!