At numerous locations, often in big cities, regular WordPress-themed meetups occur. Anyone can run one and those attending can be anybody from bloggers to developers, with all levels of knowledge. However, probably the biggest in the UK is the appropriately named Big WP, held in London. Less regular than some others it, none-the-less, attracts a big audience and some impressive speakers.
For this meetup, the first in a while, I’ve attended – my first Big WP.