Prior to this, Android 5.0.1 factory images for the Wi-Fi only Nexus 7 (2013), Nexus 9, and Nexus 10 were published. The factory images for the Nexus 5, 3G-enabled Nexus (2012 and 2013), and Nexus 9 LTE are yet to be published.
As of now, there is no word on what precise changes the Android 5.0.1 update brings; though we can expect the release to bring fixes to various bugs and issues reported by Android 5.0 Lollipop users in the recent few weeks. With the release of Android 5.0.1 factory images for Nexus devices, we can expect that Google will soon announce the incremental update.
In last few weeks, Android 5.0 Lollipop has been in the news for all wrong reasons with several user reports pointing to multiple bugs in the final release.
Some of the Android 5.0 Lollipop bugs recently reported by users include a Wi-Fi bug; an SMS bug, app switcher bug; another bug that removed the very useful 'silent mode' from phones, and a flashlight bug was also reported to be affecting some Nexus 5 and Nexus 4 users.
Adding to the long list of Android 5.0 Lollipop bugs, two new ones were reported - one about the broken manual account sync button in settings, and another about frequent restart of apps in the background.