It's too early to say, but I like how fluid this is. It is built like an enterprise product. My first impressions are as follows:
1. Easy to use, and has a few use cases in mind.
What I am thinking is, for clients, I will invite them to Webvisio, and allow them to add "tasks" or feedback on what they want or need fixed. It instantly notifies you when a comment is made. No more can you do this, and any updates on this?
2. Design work. While, I am in no means a designer, but, this is a great tool to collaborate with team members or ask for feedback new products anyone?
3. Collaboration. This goes hand in hand with the previous point, but you can work asynchronously. No more, "hey I know you're busy, but can you take a look at this when you're done." communications. It saves you time, and your team members as =they can get to it later.

What I like:
1. Collaboration
2. Everything just works and it is seriously simple to use.
3. Sharable links where the commenter doesn't need to sign up. Great for when potential clients don't need access.

What I want to see:
I want to see more of web development and design features similar to ruttl. It allows the client to address certain controls that you don't initially get from a simple comment. While they can add as much details, if they are not very technical WYSIWYG. The back and forth stuff would be virtually eliminated since the client is literally showing you what they want.

Still need to test it out further, but I am excited to see what other ideas I can think of.