I work at Gatwick Airport, not for security, and have to say i find the security very good.
Since i started working at the airport my confidence in the security at the airports has increased. Anyone going airside is properly checked regardless of who they are.
This is not the first time a story like this has come out, one of our tabloids also did something similar.
To work at an airport you have to undergo stringent checking, often taking several months before a pass is issued.
I'd not worry about security in the UK, its been good here for many years.