There are different flavors of role playing and quite often, they are not compatible, from my experience at least. I've found that not having clear, understandable house rules or game rules can lead to lots of misery, spoiled expectations and whatnot. Also, I've found that some types of role play are more conducive to certain types of expectations.
A few of the things that make a game different are:
Whether or not there will be competition among players.
Whether or not all players must be on the same side.
Guided(DM) versus Unguided RP
Collaborative writing versus Gaming
Also, the number of players makes a huge difference in how the game can be played. For unguided, freestyle rp where there is no turn taking mechanism, the faster/shorter posts may work better where there are large crowds of players, than longer, slower posts - which work better with small groups(2-4 players).
Also, the playing environment makes a difference. When I first learned to roleplay, it was in a 3d mmorpg or 3d virtual world. Interacting with other characters was very natural, and you could do a lot of spontaneous things. You could use the landscape to hide and stalk other characters. You could have meetings in alleyways - not knowing who might be eavesdropping on you and so on. when I moved to forum rp, I had to adapt - dropping the things you can do in a virtual world, and focusing more on the writing aspect of it.