The BBC has become a heavy user of Google Maps in recent months. The rise in Google Maps seems to be part of an experiment by the BBC to geo-tag readers' comments where appropriate. Recently the BBC have posted the four maps below with a message attached saying "part of a trial to find new ways of showing comments."
Broadband Speed Map - this asked readers to test their broadband speed and map their location.
Tannker Driver Strike Map - a map asking for readers' comments on a strike by tanker drivers in the UK.
NHS Map - a map asking for views on the UK's National Health Service.
Festival Season Map 2008 - a map asking for comments on the summer's music festivals.
Mapping comments in this way is a useful experiment. It can be interesting reading comments based on the location of the writer and noticing geographical differences in readers' responses. Comments on websites often become most interesting though when a debate starts up. However a debate needs the comments to be displayed in a linear and chronological order. For a good example of this see the comments in the post below where I lose an argument with a Google Maps Mania reader.
There is no reason however why the BBC can't tag readers' comments on a Google Map and display the comments in a sidebar as well. Visitors to the BBC could then choose whether to follow the chronology of the comments or use the map to read people's comments in particular geographical areas.