Commercial advertising on govt's no1 website

Figures from Hitwise at the end of November showed the Met Office to be central government’s most popular website, with traffic getting on for double that of Directgov. Now I must admit, I’m not a regular visitor to the site: I tend to favour Metcheck. But with the country apparently heading for a new ice age, I thought I’d drop by, and see their prediction for the days ahead. And I got quite a surprise:

But that’s not all. Every few refreshes, you’ll also see one of these:

I seem to recall they’ve had ‘house adverts’ for their own commercial products for some time. But this is the first time I’ve been aware of third-party commercial advertising on the site.
I’m not saying it’s a bad thing. They’ve clearly got healthy traffic levels, and they’re a Trading Fund: if advertisers want to hand over cash for a few pixels of unused screen space, hey – shouldn’t they be duty-bound to accept it? (There’s more information in this press release from September… including the rather startling suggestion that their traffic peaks at 19 million visits per day.)