Speaking as a software QA person I'd guess that making the section Christmas over and above having Christmas in the keywords of so many items hoses up the search engine. Speaking as a person who used to work in retail it could also be organizational, it's possible they recycle the Holiday section on their website for which ever holiday is prominent at the time in much the way the recylce the seasonal section of their stores.
I don't see any accomodations to PC. The Holiday page has the word Christmas on it 5 times, if they were going PC they'd call them "trees" and "bouquets" not "Christmas trees" and "Christmas bouquets". I don't see anybody on this thread that thinks PC Christmas is a good thing, I see lots of people on this thread that look at the WalMart page and don't see any PCing.
PC is like a steady drip...it just slowly erodes away at traditional, usually Christian, expressions, until they are somehow gone.
Just go to Target or Costco and see how many things have replaced Christmas with the generic phrase "holiday". In their case it is intentional.
I fear Walmart is beginning down the same path.
As a stock holder, I feel responsible to point out that their current web-marketing will alienate some of their core demographic and hurt sales.