Like flexbox, this looks like a definite improvement over what we have now, but it looks quite complicated with less than ideal syntax. I imagine that's mostly to do with playing well with existing CSS (syntax and semantics) but its rather unfortunate. I looked at a bunch of the examples and found them quite difficult to figure out, but when I started with QML, I saw one snippet of sample code and immediately was able to create complex layouts myself.

Don't get me wrong, I'm glad CSS is getting better and will look forward to the day when I can use this (but lets be realistic, it'll be a while yet before enough browsers support this to be usable), but I can't help but feel that its cruft built on top of cruft and that it won't ever be as slick and simple as something like QML.

Are they really coming? I only see it in IE.