In the creation of the very first version of the Jingle Protocol, one of the main goals was to achieve a P2P enable protocol, that would depend on XMPP for routing, but would be also able to negotiate sessions and exchange content without main proxy servers like present SIP deployments.
After 5 years we still don't have any massive deployments containing and fully supported the current specifications, and even the closer to the specification ones are suffering when P2P is not possible and relay is required and there is no available ones.
SIP in the other hand is not very efficient and simple for P2P methods but is widely deployed around the planet as it is much simpler to deploy and although with higher costs, can provide media connectivity.
Jingle Nodes comes in place with the goal of making more nodes available, as every buddy in your contact list could be a potential Node, and specially makes the task of having public relays close to trivial, as you just need to run an XMPP client with a Public Node Policy available for everyone.
A few words about Jingle Nodes
Jingle Nodes and Super Nodes are intend to provide easy to use Jingle Relay Type Candidates that can be used in ICE-UDP and also on RAW-UDP Jingle Sessions.
Relay Candidates can provide NAT Traversal for users that don't have STUN/TURN Support, but also for users with STUN/TURN support that the negotiation failed.
What about similar architecture and approach?
The unique similar project is Skype, which is a closed and non inter-operable network.
Skype Network works in a similar way except that on Skype you can't choose whether share your bandwidth or not. And as a closed protocol you can't do anything about it.
On Jingle you can choose to share with:
* only buddies
* only whitelist
In other words you are free to choose and decide about your device and network.
What people really need?
People needs to talk. End users don't necessarily care about which protocol or connection type is being used in the call, but if it effectively has audio and with reasonable quality.
The Jingle Nodes try to promote the beauty of P2P, but without dropping the Jingle Responsibility with the end user, which is call completion.
What does Jingle have and what needs to be done?
Jingle already have specifications for Direct Media, P2P based on ICE-STUN, but it needs an extension to cover Jingle Relay Nodes.
The long term goal is to have Jingle widely deployed across the world and collaborate to this adoption by providing "easy to use" and "always works" solutions.