Valve gives developers some big reasons to add a demo on Steam
Valve have overhauled the way game demos work on Steam in some big ways, and it sounds like a really good thing for both developers and players.
Great. Can I have my coconut monkey back now?
Nice! This is particularly useful for games when the demo has different content than the final game (it's not very common, but sometimes devs treat demos more like teasers and/or prequels and have different content in them than the actual game).