HTML. Logic. You gotta keep 'em separated.
I mean, we've been writing programs for the web for years and years. One of the huge lessons we've learnt is keeping things separated, that tightly binding one part of a system to another is a Bad Thing.
Of course, the Rampaging Muppet Hordes don't learn quickly.
So, XML up to my neck (10 levels of indentation!), I carry on.