Who will win the ultimate battle for your pound? Unusually both Tesco and Sainsbury's have unveiled their results on the same day.
And they are much prettier reading for the smaller supermarket. Sainsbury's total sales have grown 5 percent, online up 15 percent, convenience stores up 20%.
Tesco meanwhile have had a fall in profits and a slide in some parts of their enormous business of more than ten percent. In Turkey, for example, sales have gone down 12%.
Tesco's boss, Philip Clarke, has invested very heavily in the UK shops, and that is starting to feed through to a better financial performance here.
That is despite as Clarke says consumers not feeling the recovery 'in their wallets'. And the company has announced today a very significant joint venture with a Chinese company, where they are taking a 20% stake in a business that is worth 10 billion pounds.
But there is no question that Tesco's dominance is under significant pressure. All of the big chains, whether Tesco, Sainsbury's, Asda, or Morrisons, are having to respond to real challenges at from the more well heeled aisles of Waitrose, and the very rapid growth of Aldi and Lidl who trade on lower prices.
Throw the transformational trend of online shopping into the mix and it is a very tough and fast changing business. Morrisons is still even to work out properly how it is going to sell online.
For many years our shopping habits have been dominated and to an extent dictated by the behaviour of the big chains. But it is far from inevitable they will all be able to adapt to survive.