[madawan]

it looks like it'll become the next standard yes. but support isn't there yet.

http://caniuse.com/#feat=flexbox

http://howtocenterincss.com/

[graup]

93.99% is more than "support isn't there yet", in my opinion. Enough for many projects at least. Obviously if you develop sites with a big IE8/9 audience you should think twice.