{{tag}} is not "valid" markup (it will pass a validator but has negative semantic value), which is even worse than mixing a little well crafted logic into your display code.
I don't seem much difference, but I also prefer when making websites to keep down the number of languages I have to know. Already html + css + js + a server side language is enough, introducing another seems excessive when your templating language could just be js or perhaps the same server side language you already use.
we do the same for our server side templating when making sites, using php for controller & model code, but also arbitrary php as the template language in the view too. it seems to work well, and avoids the need to learn something new.
