This is what I got from Sprint Community forums. For the Nexus S 4G and ICS problems
In regards to the ICS release, the development teams along with the respected manufacturers are working to insure the release is reduced of its potential bugs or glitches. And as each division goes through testing, we all want to make sure that the product can be released without issue so that we do not have a repeat of the LG Optimus or early EVO issues. As this information regarding new release dates becomes available, we will certainly keep our customers informed. We understand how frustrating this is and appreciate your continued patience.
Sprint Community: Nexus S 4g and ICS-where is it?