0-60... oh dear.
Unless you're thrashing the Clio the Fiesta is faster. On the track, well if you spend 15k on a newish standard Fiesta or 15k on a shonky Clio. The Clio will be the fastest around the circuit quite easily, but you'd have to be mad to spend that on an old Clio...woops! Yes you could argue that you could spend 15k on mods on the Fiesta, but then its 30k vs 15k. When they ST comes down in price it'll be a great track car with some money thrown at it.
Anyway, real world driving on the road the Fiesta is quicker, quieter, more refined and comfier A to B. I've test driven the new Clio 200 EDC and the Fiesta ST and I own a 230bhp/tonne ITBd 172, normal driving there's nothing in it between the two turbo cars but my 172 needs working harder. A standard 172/182 feels slow in comparison.
As an aside, have they done anything with the dash yet? I heard Ford were going to change it and I hate the massive mobile phone/radio combination they stuck in the middle of the Fiesta dash.