(Spelling mistake in the title.. fixed now)
There have been numerous threads over the years requesting that blizzard fix the lighting so we get an actual night time. They've mostly been ignore but this time a blue piped up and replied.
The EU thread on "Night time".
The US thread on "Night time" (Post capped)
The 2nd US thread on "Night time"
Now before you jump down my throat and complain about people wanting the darkness back and it might be too dark for you, please hear me out.
What I've gathered from these threads is that the majority of people who have responded (so far) want the lighting system fixed. Even if blizzard put the lighting right so that we had a night time, I believe it would be pretty easy to implement an option to turn night on/off like they do(did) with weather effects.
If you want night time back, spread the word. Hell, use the suggestion box in game if you really want it back. If enough people tell blizzard we want it back, they will eventually listen.