Well For sure Zidane is doing a much better job than Rafa...specially on the long term... but it's still gonna take him and Real Madrid Time....
Barcelona is just going through a very good phase since Guardiola's Era...But I am quite sure once Messi, Iniesta and Alves will retire (specially Messi) it will mark the supremacy of Barcelona...
I mean just looking at the stats of both teams you can see that Barcelona is just going through a phase :
http://www.real-madrid-vs-barcelona.com
P.S: I don't think Real Madrid will win this next Clasico...