Samsung has released the open-source portions of the Infuse 4G OS and made it available for download at their Open Source Release Center website. As is always the case, this isn’t something that you can download and flash to your phone, it’s code for developers to use to rebuild or tweak the system. Everyone else just needs to sit tight, and feel good that Samsung is doing the right thing without needing to be reminded for a few months — or years.
If you are the developer type, you can hit the source link and search for SGH-I997 to get to the download and release notes. Then get busy!