I had a survival world in which I hadn't slept in over 3 days (so phantoms were spawning), then I got the 1.8.0 update.

I found another bug while playing (it has its own Issue page), so I made a creative copy of my world to isolate it.

I spawned in survival mode (I thought I was supposed to spawn in creative mode?) and used /gamemode 1 to switch to creative.

After night fell, phantoms started to spawn.

I think this is a bug because it would be annoying to have to sleep in creative (especially if you want to see your build at night), so this is a bit like phantoms spawning in the end or nether (because you can't sleep there).