Website is up for info on this class action settlement.
Deadline for filing a claim: August 28, 2012

https://www.iphone4settlement.com/Default.aspx

Info from home page:
"To be eligible for the cash payment, you must have: (a) experienced antenna or reception issues; (b) been unable to return your iPhone 4 without incurring any costs; (c) been unwilling to use a case or free bumper for your iPhone 4; and (d) completed certain troubleshooting steps or are unable to complete the troubleshooting steps because you no longer own your iPhone.

The settlement will provide a $15 cash payment if you are a United States resident who are or were the original owner of an iPhone 4, and who experienced antenna or reception issues, and satisfy other requirements explained on this website.

Since July 2010, Apple has offered a free bumper to iPhone 4 owners who have experienced antenna or reception issues. Class Members can continue to request a free bumper as described at http://support.apple.com/kb/HT4389."