Big winners and losers from cold snap
BBC business editor Robert Peston on chill winds for 2011
It's fairly clear that the important Christmas trading period has created something of a hierarchy of retailers.
At the top (no surprise here) are the giant supermarket groups.
Some may have been net beneficiaries of the appalling cold snap.
Well, we all have to eat; and if we went out to shop at all through the deep and treacherous snow of December, we probably went to Tesco, or Sainsbury, Asda or Morrisons.
And when we were in the supermarket, we may well have spent more than usual on clothes, DVDs, CDs, electrical items and the baubles that go into Santa's sack, to save ourselves a horridly frozen trip to the High Street.
Which means that the supermarkets may, in the round, have taken more money than normal.
And it explains in part why the performance of HMV has been so lousy and why Next says that it lost £25m of sales to the elements.
Against that backdrop, Marks & Spencer is also likely to have suffered.
The apparent anomaly is John Lewis, whose remarkable sales growth seems impervious to any kind of climate.
One question, for when the dust has settled (and the snow has stopped settling), is which retailers are experiencing serious difficulties unrelated to poor weather.
HMV is plainly facing a structural challenge: competition from the supermarkets, online retailers and digital downloads is intensifying, though that threat was camouflaged to an extent till recently by the windfall HMV received from the collapse of Zavvi and Woolworths (and the demise of Woolworths was a double boon for HMV, because it disrupted wholesale distribution to supermarkets).
With the rise in VAT dampening consumer spending, and households' fear of interest rate rises a potential second dampener, 2011 is likely to be one of those Darwinian years, which sees the extinction of retailers genetically incapable of surviving a long economic winter.
You can keep up with the latest from business editor Robert Peston by visiting his blog on the BBC News website.