I've had a Jaiku account now for a couple weeks, I really like it. It's a one stop shop to answer a question someone may ask you like "What do you do online?" Or "What do you like?" Or "Where's your stuff?" Increasingly many people have many different things spread throughout the internet. Bookmarks, playlists, blogs, etc etc. I've gone the extra step of building my website around the fact that there is no central repository of a person online anymore, and it allows me to add things as more things show up in my online life. So it's the one place people can go.
With Jaiku it's the same idea. A stream of a person on a simple page. Songs, bookmarks, blogs, photos, whatever. It's a good place to send people to check out what you're about without giving 10 different URLs.
Mine is at http://gabek.jaiku.com/. Check it out. Do you have a Jaiku?