I use nothing but Linux and visit BBC's site regularly. However, I use konqueror which is set to identify itself as internet explorer to fool the Microsoft drones (a lot of sites block you unless you sell your soul to the vole)! I suspect I'm not the only person doing this so I wonder how they can be sure of any statistics. 

Why can't I access the BBC streams with my BBC Micro? Seems like they don't even support their own formats.

You didn't sound right, so I tried the BBC's front page video for today ( Saudi audience at Vatican) and, I got http://news.bbc.co.uk/2/hi/help/3681938.stm
which tells me to get a WinPC or a Mac. So, W-, what's your secret? Oh, now I understand, "W-", that's, uh, sarcasm?

Having to use RealPlayer on BBC sites to play virtually all of the BBCs multimedia content has been the bane of linux users for several years now. Despite being frequently requested to change to a non-proprietary cross platform format such as mp3 or ogg, the BBC has consistently stated that it has no plans to provide alternative formats.
Fortunately, it usually provides direct links so streams can be played in non-realplayer software, but its just more evidence of a M$ centric philosphy.

Imagine how many more Linux users would visit the BBC's site if all the content was available via cross platform technologies...

Which is why open standards should be adhered to. That way anyone can join the party: Linux, Mac, MSFT, your cellphone, etc.

I access the Beeb site fairly regularly using Linux. Seems to work just fine.

99% of the content is accessible by linux you know, even linux has a web browser, and has players for non-DRM'ed video/audio formats.
Plus the BBC agreed to make that 'recent tv' thing more multi platform, so they are at least trying a bit.