You're basically correct. RDP can model and transfer data semantically - i.e. it's not just pixels, but higher order objects like toolbars, buttons, and the li

You're basically correct. RDP can model and transfer data semantically - i.e. it's not just pixels, but higher order objects like toolbars, buttons, and the like. VNC and most others just do raw image/video transfer, with whatever codecs and compression they choose. Of course, RDP can only use semantic data for apps that support it, and it makes sense these would be official MS apps first.