It's fairly easy to download all the pictures again with the API, though you'll find there all a maximum of 604px x 604px. The linkage and tagging is the harder

It's fairly easy to download all the pictures again with the API, though you'll find there all a maximum of 604px x 604px. The linkage and tagging is the harder thing to export. I know exporting the tagging is at least doable. Hiding the defriending process is pretty common, if not universal across all social networks. I suspect the lock in isn't really that great, people only really care about the last few weeks in most cases. The main lock-in is that your friends are still there even if you leave. Ultimately I think people won't need to leave networks like this when they become active elsewhere, they will instead use aggregation to keep track with their friends on the old networks (for example in my product http://friendbinder.com http://friendbinder.com) or possibly built into to new networks if they work how to do this properly.