And does "celebrity-manned" mean "celebs-present"?
The BT Tower is a London landmark that is recognized the world over – it is one of the most recognisable sights in London. The BT Tower is one of those sights that many London tourists are keen to take a photograph of during their visit to their city. The building has achieved such iconic status that in 2003 it was awarded Grade II listed status. The BT Tower is located in Fitzrovia, in central London.
The BT Tower’s status as a building of national prominence is reflected by the fact that a made-of-lego version of the building appears at Legoland. The tower is perhaps best known to many people as hosting the celebrity-manned BBC Children in Need phones each year. The BT Tower has appeared in many films, including ‘Harry Potter & The Chamber of Secrets’.
...And, as the original quote suggests, there are differnt grades. Some private houses are listed, and their status limits what changes can be made architecturally.