I have had one of my web surfing nights - they tend to come in waves! I have joined up with a fair few sites - partly because you need to do that to see what they are all about.
It is a social networking site with similar features to MyBlogLog. A major difference is that to join a community you must be approved. The advantage of this will be that although you may not be able to join a community you can browse them and know that the bloggers therein are knowledgeable about their subject and the subject matter is relevant to its community.
At present, apart from a general community that all join on registering, the communities are all based around affiliate marketing and SEO. Fellow bloggers may find the information of use for optimising their site, bringing in more readers and monetizing.
Even if you are not interested in this, the site is worth checking into from time to time as more community categories are going to be introduced.