Commercial Breaks & Beats

I know that recently the Gnarls Barkley track was used for BBC Radio 1's TV advert but just before that (and I think it's still showing) there was a guitar based track. Quite an uplifiting and melodic song but I can't find out anywhere who it was by.

I was in my brothers car and I'm sure the song was playing on the radio and I just caught the end of it, I think they said it was by The Feeling but we had the windos open and it was quite noisey so I'm not sure.

Any clues?

"The Feeling - Fill My Little World"
...for Chris Moyles, really recent

or they have used
"Kaiser Chiefs - Na Na Na Na Naa"
for general shows and Zane Lowe