Full list:
Michael Buble - Cry me a river intro
Frankie Goes to Hollywood - Two tribes (air raid siren)
Van Halen - Runnin' with the Devil (second siren) into a Custom bass guitar beat mimicking the one that follows the siren at the start of the same Van Halen track.
The FGTH and VH tracks were added back last year as a nod to the WNIR intro as it was our 30th season.
Nickelback - Burn it to the ground (this is a loop I made of the riff for clapping purposes, it's not as per the original).
Rev Theory - Hell Yeah
That's the lot.
Previous versions have indeed used Hans Zimmer's 'Contender' theme (pretty much the whole Gerad Adams era) but also Steve Jablonsky's 'Autobots reunite'. I did use Jablonsky's 'Scorponok' for a while but it seemed only Aled would have been able to drum along to it