I'm not sure what exactly is going on with the Dr Who Experience. Perhaps the BBC think they can make more money moving it to London? (or doing a travelling exhibition?). Perhaps something has come up for that land?
There is a simple reason why the building is proposed for Brittania Park. I think it is the only land that ABP owns in the bay area that is not still used as industrial/port facilities: the Dr Who site, Porth Teigr, etc, were all sold off (to the Welsh Government, I think) some years ago. So ABP can only really propose a development in this spot if they want to realise some value from (non-industrial) development.
http://www.abports.co.uk/admin/content/ ... ardiff.pdfI think with high quality materials the main development would look good. I'd be tempted to refuse permission for the various smaller buildings though as they do appear to be an over-development of the site. And I'd put very strict conditions on materials given the prominent location, and the size of the 'side on' view (if its bad, its a lot of bad to look at!).