Ignore everything that's not the wallpaper or the taskbar, those are the only items that got touched by the KDE VDT for now. The Windows are still using the old Oxygen theme.
Awesome! That theme looks like a huge step forward. Overall KDE still feels a bit cluttered to me, but at least that clutter won't be so ugly anymore soon!
No ETA, as far as I know. I think the plan is to ship it with the second release of KDE5, but it's information gathered from the forum, not official words.