According to the latest post in GW7AAV's informative and often dryly humorous blog, the RSGB has written to Ofcom raising concern at the release, in full, of the database of UK amateur radio license holders on its web site, which was done following a number of requests from radio amateurs for the details to be released under the Freedom of Information Act. Apparently, the RSGB’s main concern is the security of the details, which can now be downloaded by any individual, radio amateur or not.
As far as I know, the RSGB Amateur Radio Callbook can be purchased by any individual, radio amateur or not. So I can't see how anyone's security is being compromised more than it is already.
The availability of the callsign database in machine readable form means that it would now be possible to find out who owns the antennas at 21 Acacia Drive, Surbiton, or list all the amateur license holders in Cockermouth. But there was a callbook CD given away by Practical Wireless a few years back that allowed searches by name, town or postcode. I distinctly remember using it to find out all the licensed amateurs in the CA13 postcode area. So nothing new there, either.
Could the objections have more to do with the effect that making this data freely available would have on RSGB Callbook sales? Surely not.