Well, the idea is that you submit topics from your favorite forums in order to get more visibility, more members. It's free targeted advertising. Every website, in order to succeed, needs to be found by targeted viewers.
Anyway... The site is called Hot Topics Live..
Hot Topics Live - You see a topic that you want more people to read about and/or give their input on - such as the discussions about the federal government taking over the supplement industry - and you post a "social bookmark" to that discussion. Other people go to the site to check out the latest "forum" hot topics, they see yours, they vote on it - and eventually, if it's an interesting enough story, it makes it to the front page.. Once there, it becomes very popular and the site gets lots of traffic (the intended result of any webmaster)..
What's good? It's free.. What's not? It's new - so it's not very busy yet. But, the site IS getting a good amount of traffic.. You should give it a shot...