As others have said, the song wasn't particularly groundbreaking - Addicted to Bass did it better a couple of years prior, and Sugababes were already around as the "edgy" girl band. What it did show was that Girls Aloud were likely the Real Thing and would have an actual career. As Popstars the Rivals (the show that created them) was heading towards the final, it was generally assumed that the boy band would be more successful than the girl band - there was a gap in the market for a British boyband which was to be managed by Peter Waterman (who at the time was still seen as a pop svengali, rather than a washed-up out-of-touch former hitmaker).

When the rivals songs were released though, it was immediately obvious that girls had the far superior track and outsold the boys by a healthy margin to grab the coveted Christmas No1. The song also ended up defining Girls Aloud's sound (fun, dancey, catchy, a little different - as opposed to ballad-heavy, earnest, or showcasing vocal gymnastics) and cemented their relationship with song producers/writers Xenomania. (In contrast, the boyband followed up their boring mid-tempo song with an even more boring mid-temp song, then promptly disappeared).

As others have said, you should definitely check out the various incarnations of the Sugababes who were doing this kind of stuff earlier.