Aren't all world-facing websites "a public service"? BBC within UK has a special remit because of the funding structure (thanks to the increasingly-inaccurately named "TV" licensing fees), but BBC [Worldwide] is just another content provider in the big old crazy world.

It doesn't seem surprising that BBCW use an external advertising network: it would be a pretty huge investment to operate their own advertising markets throughout the world ... and surely if they did, they'd then on-sell those services!

Seems that the notable part of this attack is that several high-profile websites were affected, so BBC (and NYT, and AOL, etc) suffered some damage to their brand, so they'll have to work on that. The article notes that "malware was delivered through multiple ad networks", which speaks to failures by those service providers. Reckon there will be some very heated conversations and perhaps fee renegotiations with the networks happening over the next few weeks ;-)