UK's favourite airports:
Heathrow - favourite with 67 million people a year
Gatwick - 32 million a year
Stansted - 22 million
Manchester - 21 million
the next few, not so popular on about 8 million (ish)
Birmingham
Glasgow
Edinburgh
Luton
etc etc etc
Any other kind of 'popularity' rating is just tosh.
It's a bit like the old one about Tesco's 'no-one ever shops at Tesco's because of all the queues'. There are only queues because EVERYONE shops there!
Cheers,
TheOddOne