The supermarket war for market share over Christmas was brutal, but the fight for consumers’ online mind-share in 2012 will also be intense, with Facebook a key battleground.

If we look at Facebook’s 30 million UK users, the communities the supermarkets have built on the network remain modest. The top nine food retailers have around 1.3 million ‘fans’ between them, a tiny proportion of the Facebook users who walk through their doors.

After an initially glacial approach, in recent months we’ve heard one supermarket chain after another publicly boasting about their budgetary commitments to social media. Finally, the gloves are coming off.

An interesting illustration, though by no means an exhaustive one, of where we currently stand is to compare retailers’ real-world market share with their proportion of fans on Facebook. Perhaps unsurprisingly, Tesco leads the pack with just under 500,000 fans, a 40% share of total supermarket fans, representing a 10% uplift on its market share. Sainsbury’s - on 320,000 fans - is likewise outperforming by a 10% margin.

In contrast, Asda is playing social media catch-up, with just 82,000 fans, a 7% share of Facebook fans compared to its 17% grocery market share. Morrisons is also trailing, under-represented on Facebook with just 45,000 fans. Interestingly, many food retailers in the second tier are punching above their weight. Iceland has an impressive 82,000 fans and Lidl 67,000.

As we are always telling new clients, raw follower numbers are important, but what you do with them even more so. How will you keep fans coming back to your page and how will you engage with them there? Waitrose, with 38,000 fans, delivers a masterclass on creating an attractive Facebook destination which goes beyond bog-standard competitions and promotion advertising.

It has integrated its marketing across channels better than most and, crucially, realised the importance of video. Its dedicated YouTube channel, with almost 3 million video views, is streets ahead of its nearest rival Tesco, with only 620,000 views.

Tellingly, almost a million of Waitrose’s video views came from a single clip of Heston and Delia delivering their School of Christmas Magic. Sainsbury’s, too, has a huge opportunity with new ambassador David Beckham to create bespoke video content that could help drive both Facebook and YouTube growth. Let’s see if that was negotiated into his reported £5m contract!

For supermarkets and social media, 2012 will be a crucial year - but there is still everything to play for!

Daljit Bhurji is managing director of integrated social media consultancy Diffusion.