That Ning now no longer supports free networks has been compared to blackmailing by some.
I also think so. But to be blackmailed there are two factors:

You have the choice: Only use a service which at least provides a way to get your data out. (To be fair, it seems Ning will be offering this according to the blog entry cited above, but the details are still unclear)
But: The data alone is nothing without the software. So you need a service where you can export the data and have open source software available to do something with the extracted data. But the first part is the crucial one: If you have only the data, software can be written…
I’ve written earlier in this blog (and talked @Manchester) about the problem of vendor lock-in in “cloud computing” which is almost the same as “web 2.0 services”, namely software as a service (SAAS). Ning falls into that category as do other social network services like facebook or Xing.
This boils down to what the open cloud initiative has defined as cloud computing openness: For open content you ideally want to go for a free cloud with open APIs, open formats, open source (software), and open data.
Note that facebook is no alternative to ning: People have been thrown off facebook for retrieving their data, cited in these two entries on Henry Story’s blog.
But the choice has to be made by customers (or non-paying users) of these services: Don’t use something where you lock in your data. Or your data might be at risk, or locked in, or dead.
Doc Searls, co-Author of Cluetrain Manifesto and Editor of Linux Journal has written about this in a blog entry called Silos End: “These problems cannot be solved by the companies themselves. Companies make silos. It’s as simple as that. Left to their own devices, that’s what they do. Over and over and over again.”
Ideally there would be a standardized service and hosters agree to use the same software (maybe customized in the appearance) to host services for users. A hosting standard for collaboration software. Starting with the services Facebook, Xing, etc. are offering today. We want an interchange format that everybody can use, export, import.
I think a standard for these types of services will leave us with a network of hosters. This — in comparison to the status quo today — will be a distributed system, maybe a peer-to-peer system, not some big players locking in users. A common standard will hopefully keep the players honest.
To get there: Lets try to evaluate replacement software for Ning. Work on interchange formats. A suitable format for contact information is the Friend of a Friend (FOAF) format endorsed by the W3C, this is part of the semantic web effort.
One software that comes close to this goal might be elgg — I’ve not tried it myself, but there is already a group of Elgg Service Providers which comes close to the goal of a support infrastructure built around an open source project.
I’ve two points of critique, one of them being more personal taste, the other related to the license. The first is that the software is in PHP. The license is the GNU General Public License which offers no protection against a service provider making own modifications to the hosted software and not releasing these modifications as open source software. Details are in my earlier article on the subject. So far, the team of elgg seems to play the game very open. The Source code with (yet) unrelease modifications to the software is freely accessible as a subversion software repository. Furthermore they offer nightly builds for download.
There are many other good points, too: It offers syndication with RSS and JSON, and has an API to interconnect with software running elsewhere — which are the basic ingredients for a distributed system. The API is Representational State Transfer (REST) that happens to be the same mechanism on which the semantic web can be built.
So lets take some steps in the direction of a system built on standardized components where no vendor can lock us in.
When we get there, we’ve left Web 2.0 behind. The future is a distributed system, lets call it Web 3.0.