I’d agree that Unionbook has a limited value as an organising tool, mainly due to its scale – but I wouldn’t write it off completely. I could see how union organisers could use it to get the word out about a campaign or mobilisation, knowing that those who receive the message are (probably) dedicated trade unionists who at the very least can be relied on to spread the message through their own networks (probably then using facebook et al to do so), turn up to events etc.

But like you say, I think unionbook is less a campaigning/organising tool and more a social networking tool for trade unionists – which is useful in an of itself.

Unionbook seems very limited to social networking between unionists (which I understand is its purpose).