The Google pushed a new version of Android for their LG Nexus 4 smartphone, upgrading to 5.1 (I was previously at 5.0.1). I am happy to write that this upgrade was smooth and eventless. The last time I had trouble was in June 2014 going from 4.4.2 to 4.4.3. The three subsequent upgrades (four counting this one) were much smoother.
So if you want to know what to expect going from 5.0.1 to 5.1 before you attempt it, here is what I experienced… (please note that I am pruning the screenshots to only shot relevant information, in order to keep this fairly short)
The System Update notification gets you to the Download screen. As you can see, this is a 174.5MB file.