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It surely is!! I've written several rants already about the lack of window tiling in modern window managers, and i'm very pleased there's a major DE implementing such features.
I haven't had the pleasure of trying it out yet though, still waiting for kubuntu packages to appear [hint hint, kubuntu developers].
Well, it is quite basic for now, only 2 layout are supported, so it is not very useful yet, but I hope all classic layouts will be supported soon, titlebar disabling and settings per vitural destops or activities will be supported.