When do you need the most electricity?
When deciding what direction your solar panels should be facing, an important question to ask is when will be using the most electricity?
An East-West orientation will, as already stated, provide the most electricity in the morning and evening times, while a South facing orientation will provide more power overall, spread throughout the day.
If you want to make hot water using a solar thermal system, or a power-diverter with solar PV panels, then having east facing panels will be ideal.
This will give you the most power during the morning to heat water to start off your day.
For household solar panels, if the home is going to be empty most of the day while the occupants are at work, or otherwise out, it might not be the most useful to have that power going to waste.