You see them at LAX airport in the second week of June every year, long snaking lines of them, sloping off long haul flights and waiting to pass through customs. They're mostly men, mostly in their 20s and 30s, dressed in jeans, T-shirts and trainers; they're in big groups, laughing and joking, enjoying the air of jubilant anticipation, but pretending not to. They're all here for the same thing; the same thing 50,000 other people are coming to Los Angeles for; the same thing I've now been doing for 10 years. E3 – the electronic entertainment expo – is effectively the Mecca of the mainstream video game industry. Held every year at the vast Los Angeles convention centre (except for a couple of ill-remembered jaunts to Atlanta, and two years when it was semi-cancelled), it is a trade-only event that everyone in the business has to attend at least once.