... now with minimize support.
KWin tiling has been proceeding forward at a steady rate. If you check out the latest revision, you will not only have a pretty stable experience, but will also get a design document for free.
So orientation is horizontal and vertical, and ratio is how much space the left child gets. Using these two properties I expect to be able to do most layouts. For now you can use D-BUS calls to actually use tiling pretty well.
Here are the calls
qdbus org.kde.kwin /KWin slotToggleOrientation
qdbus org.kde.kwin /KWin slotSetRatio <float> # between 0 and 1
qdbus org.kde.kwin /KWin dumpTiles # get a nice tree if you have debugging enabled and visible
Some applications will cause trouble. Especially some plasma widgets and Kruler aren't setting the right window attributes, so I can't exempt them from tiling. So don't launch panel settings or Kickoff menu, it won't look so well.
Minimize and restore works now, it will keep track of where the window was before you minimized it and put it back there.
Please leave feedback about bugs here or on the KWin mailing list, it will be appreciated.