Unless Microsoft's playing a nasty trick on its loyal fanbase, the latest Zune newsletter confirms a feature-laden software update, very likely what we've been calling Zune 4.0, is due out on Tuesday, September 15th, the same day as Zune HD takes its place among its fading peers. "All-new Zune software packed with exciting new features," you say? We'll be looking forward to more HD video options and an apps marketplace, all the while bemoaning our cut in HDTV Media Center recording capabilities. As for any other surprises, looks like we'll just have to wait and see -- for now. Full Zune newsletter reprinted after the break.