[B Knotts]

According to this article, she doesn't wear it regularly; she wore it when she met Pope John Paul II, as protocol demands, and then wore it at the Vespers service held in London after his death.

Revealed: Tony Blair's Catholic secret

Still, many Britons didn't like it:

In the pews, the editor of one Catholic newspaper turns to the chairman of another.

Editor: "Is Cherie wearing what I think she's wearing?" Chairman: "Good God. I haven't seen a mantilla for 20 years."

...

After the service, however, many worshippers were still fixated on the mystery of Cherie's headgear. Wearing a mantilla in London is the equivalent of a modern City banker sporting a bowler hat - a head-turning anachronism.

"I know she's proud of her faith, but she didn't have to rub our noses in it," grumbled one Catholic grandee.

FWIW, I think it'd be good to see British bankers wearing bowler hats again...I guess I'm just old-fashioned. :-)

[Wessex]

I shall have to go and take a peek at Mrs Blair's headgear in the Oratory one Sunday. It could be that the future of tradition in England rests on that solitary head!