Twitter isn't ideal for people who prefer to abstractly snipe into a discussion(which is the overwhelming tendency of hobbyist forums) because it's too personal. You have to follow a whole person, and take in their whole set of interests, and reply to them specifically if their remarks interest you. So for obscure hobbies, starting the conversation becomes much more difficult than on a dedicated site - plus take into account the relative size of the whole Web vs. Twitter.
In exchange for this weakness, Twitter gains vast influence in topics that have some critical mass of interest. Creative fields are an obvious pick - art, music, writing, programming, journalism, video games, among many others - all share a special space on Twitter. The professionals in the field have an easy time networking on Twitter since it's very informal and has "degrees" of friendship built in (comment, follow, follow-back). Plus if they're independent(which is the case for a lot of these creative fields) they have no corporate masters to hold back their thoughts; so subsequently, industry news and rumors flow through very readily - retweeting and hashtagging act to spread a single discussion across many otherwise removed individuals. This is where things get interesting, because it makes radically different perspectives collide with alarming frequency - it can't happen like that on a single forum because the "minority" or "unprivileged" perspective gets suppressed at some point.
Lifestyle and subculture topics are similarly hot on Twitter because they involve the whole person and how they choose to define themselves...often people on Twitter will converge into groups of friendship by transitioning from the "interest topic" to the people involved.
In exchange for this weakness, Twitter gains vast influence in topics that have some critical mass of interest. Creative fields are an obvious pick - art, music, writing, programming, journalism, video games, among many others - all share a special space on Twitter. The professionals in the field have an easy time networking on Twitter since it's very informal and has "degrees" of friendship built in (comment, follow, follow-back). Plus if they're independent(which is the case for a lot of these creative fields) they have no corporate masters to hold back their thoughts; so subsequently, industry news and rumors flow through very readily - retweeting and hashtagging act to spread a single discussion across many otherwise removed individuals. This is where things get interesting, because it makes radically different perspectives collide with alarming frequency - it can't happen like that on a single forum because the "minority" or "unprivileged" perspective gets suppressed at some point.
Lifestyle and subculture topics are similarly hot on Twitter because they involve the whole person and how they choose to define themselves...often people on Twitter will converge into groups of friendship by transitioning from the "interest topic" to the people involved.