It's been out since the 15th. I don't think it added anything major, just a few minor bug fixes.
They claimed to have added an XCOM 2 SLI profile, but they clearly didn't spend 2 seconds on it. Prior to this driver, you could force AFR 2 and get it to work just fine, with the exception of the cover icons disappearing. This SLI "profile" for XCOM 2 breaks the cover icons as well, so it's clear that all they did was turn on AFR 2.
I'm actually pretty disappointed with Nvidia. XCOM 2 is one of the bigger PC exclusives to come along in a while, and there was no game ready driver, and we still don't have a real SLI profile? While SLI has always had its quirks, I feel like Nvidia's efforts in supporting it have fallen off recently.