One of the Migration Information Source's Top 10 Migration Issues of 2011 is "Immigrant Detention under Scrutiny in Australia, United Kingdom, and United States." There have been some recent shifts in Australia's detention policy; the government has decided to begin releasing asylum seekers who were detained because they arrived by boat. At the same time, IRIN recently reported on the mental health consequences of detaining asylum seekers for extended periods.
In the U.S., the New York Times just published an editorial characterizing the immigrant detention system as "broken," despite promises by the administration for reform. A recent PBS FrontLine programme that investigated immigration detention practices has received a lot of attention; see, e.g., the blog series that the ACLU has been running since the documentary aired. See also this recent report from LIRS.
In the UK, children are still being placed in detention even though the government vowed to end the practice. Charges of deliberate misrepresentation have been leveled at officials in the Home Office and UK Border Agency.
Elsewhere, NGOs in both Europe and Asia/Pacific have also called for an end to the detention of immigrant children.
For more profiles of detention policies and practice in different countries, visit the Global Detention Project.
The International Detention Coalition has been hosting workshops in the Americas, South Asia, and Europe to map detention in the various regions, raise awareness and develop action plans.