I recently joined Jaiku because I was looking for a way to automatically publish updates from my various online projects. If I posted a photo to Flickr or the photoblog, I wanted a way to update this site without having to create a separate post. Jaiku lets me pull the RSS from any site I want and place it here. You also get a nice page with all of your Jaiku updates and feeds rolled together. So I added the feeds for my Flickr account, photoblog and photogeekery.com. If you click on the links on the sidebar under “What I’m Up To” they will take to to the relevant site. So Jaiku is a simple and free way to pull together everything that makes up your online presence. It’s like twitter, but more useful. 
Jaiku isn’t without its bugs though. After I signed up I wasn’t able to add any feeds to my account. That little issue didn’t resolve itself until the next day.