I chose to use Symbaloo for my PLN and it's slowly coming along. I like how you can create a number of different webmixes. That appeals to me because I like to organize things by categories, or its relevancy to each other. I could have a "social networking" mix, a "travel" mix, a "music" mix, and so on. I'm still in the process of customizing it all. I added the "EDU Tools" webmix as well. I haven't explored each tile in that mix just yet. There appears to be a lot of useful tools on this grid though.