Still not official word on the release of Ice Cream Sandwich. However the new Galaxy Nexus is confirmed to come loaded with the new Operating System. You can sign up for updates at www.sprint.com/lte. Sorry I have more information at this time. When it is made available or an announcement is made, there will likely be a blog posting here in the community.
ICS for the Sprint SGS2 is still in testing. It's not 100% done but from what I've personally seen (as I've run every single leak that's been out) it's comming along nice. Give it some time we will be getting the update but from the last build (FC07 which as of right now is the most current "leak") it still has a few issues with it that do NEED to be resolved. We are going to get it however just again as I said give it some time it is being worked on.
@E_Ack - Samsung released a statement on Twitter that they have no offical release date for ICS in the US for SGS2 phones. Once the update is availble, we will post information in our forums.