The chorus to a John Denver song I was never that keen on keeps looping around my head: "'Cause I'm leavin' on a jet plane/ Don't know when I'll be back again/ Oh babe, I hate to go/ All my bags are packed and I'm ready to go."

It's been six years in Beijing, and my local friends and colleagues generally respond as if I've cashed out and I'm going to a better place - namely, heavenly Hong Kong. "You lucky thing," they say, their voices invariably rising as they say it. Some haven't yet visited the special administrative region, but they seem to believe that it is a better place than where we are right now.

They list the capital's negatives: pollution, traffic, weather, house prices and possibly healthcare and education. Perhaps they suspect these are the reasons I am leaving, since I haven't been fired or even fallen out of fascination with the city.