As Sprint Nexus 4G owners are probably well aware, the GRJ90 update scheduled for yesterday never went out. For one reason or another the system update comprised of mostly bug fixes (and possibly bumping the Android version up to 2.3.5) was deemed not ready for prime time. A new date has not been set for the updates rollout at this time.
In related news, the EF09 update for the Samsung Transform was pulled after widespread instances of the new system file failing to install. Samsung is working on a fix with a proper update hopefully on the way in the near future.