15/12/2014 19:08 GMT | Updated 14/02/2015 05:59 GMT

Christmas Streamers Add to the Festive Spirit

It's that time of year again. I'm A Celebrity... is a fading memory, the BBC has just crowned its Sports Personality of the Year and a previously little known member of the public has become a pop star overnight by winning the X Factor final.

But after all of those public polls comes the greatest and most traditional of all - today, the race to score the Official Christmas number one begins in earnest.

In 2014, X Factor winner Ben Haenow faces one of the most competitive races for years, with a range of huge records in the mix. For a start, there is a genuinely huge pop hit already in the box seat - Mark Ronson featuring Bruno Mars' Uptown Funk, which is the reigning number one on the Official Singles Chart.

In turn, the team behind 2012's number one by the Justice Collective (in memory of the 96 victims of the Hillsborough disaster) are back with a World War I commemorating version of All Together Now, as the Peace Collective. Plus, of course, Band Aid 30 has returned with a selection of the biggest pop stars of the era - and then there is the phenomenon that is Ed Sheeran, with the two-time number one Thinking Out Loud from his massive X album also competing. And that's without factoring in campaigns to get Iron Maiden, electro outfit LFO and even Peter Andre to the summit. You can see the full list of Christmas Number one 2014 contenders here.

The Christmas number one race provides a continuing fascination for labels and artists alike, perhaps understandably. With singles sales continuing to be at an historic high in recent years (over 180m in each of the past two years), the Christmas week provides the biggest haul of all. To music fans too, the Official Singles Chart is among the UK's highest profile public polls - and Christmas number one week is the most high profile of all.

There is a significant difference about this year's race however - an historic difference, truth be told. For 62 years, the Official Christmas number one has been decided on the basis of sales alone. This year, the race reflects the changing way that music fans are consuming music.

In July, the Official Singles Chart began counting streams for the first time - 100 streams being counted as equivalent to one single sale, with each user limited to a maximum of 10 streams a day. So, for the first time in history, the consumption of music by fans who have switched from buying downloads or CDs to streaming music via services such as Spotify, Deezer, Google Play, Napster and O2 Tracks will count towards the Christmas race too.

Already, it is clear that this will be the biggest Christmas for streaming we've yet seen. A year ago, the number of streams tracked in the UK rested at about 170million a week - today it is closer to 350million, as more and more music fans engage with their favourite sounds in an entirely different way.

And just a week ago, the Official Charts Company revealed that 18million streams of Christmas songs were delivered in the first week of December in the UK, indicating that Christmas parties across the nation were being powered by these new generation digital music services.

Music sales will still play a huge part however. Christmas is always a big time of year for physical releases - it is more difficult to send a gift of a download or a stream, after all. Wrapping is not easy.

Plus, the music market inevitably moves more mainstream in the festive season - and mainstream music serves a larger proportion of casual music fans, who in turn are less likely to be streamers or downloaders of music. In this week's Christmas number one race, Haenow's Something I Need, the Peace Collective's All Together Now and Band Aid will all be represented by a CD release, for precisely that reason - to make the singles available to the broadest possible audience.

Who will win out at the end of the week is anyone's guess though. Last year, Sam Bailey's Skyscraper romped to the Christmas number one spot with almost 150,000 sales - and Haenow is similarly set up this year, with the X Factor final's TV audience reaching a similar level as last year.

But initial download sales suggest Uptown Funk has a genuine chance. In turn, the Peace Collective kicks off its campaign at the Houses of Parliament today and the Band Aid 30 release will also be an obvious gift purchase for many.

The race is on for another year!

And in the meantime, you can remind yourself of every Christmas number one winner ever right here.