The US is going to check the information of immigrating passengers on the social media.
The Guardian: US border control could start asking for your social media accounts
The US border control will introduce an additional question about the applicants' social media account. It will be optional for a while, but will be expected to ensure the validity of border control.
Actually, some terrorists make use of social media to recruit their allies. Other crimes including illegal deals are also done on the internet. It is essential for the US and other countries to examine the activity on the internet of suspects for preventing their illegal acts.
This attempt looks quite experimental, because applicants can tell a lie, or refuse about disclosure of their social accounts.
On the other hand, it is possible to identify each applicant's social account in real time. I believe some information agencies have started the constant censoring of doubtful activists.
Anyway, this legislation is annoying for most normal travelers. Recently, American Airlines attempted to let persons with a high score of Klout, an indication of the influence on the social network, use a VIP lounge. Such a usage is cooler as a way of utilization of social media, I think.
MashableAsia: How Klout Can Score You the VIP Airport Treatment