There are multiple forms of RP, so it depends on what you are looking for. I would recommend you look at various guilds to see what they declare as their preferred RP style.
For example, in the Duchy Of Wessex His Majesty has publicly stated our role play style (
http://duchyofwessex.org/forum/showthread.php?6-What-form-does-quot-role-quot-play-take) going all the way back to the original Darkfall. Here is an excerp:
Think of it - we have all of these roles from medieval society actually doing their real jobs in game. This will make a setting for us where, when we talk about "Sir Cennic of Clogrotto", we will not just be saying needless fluff, but will actually being communicating real and necessary information: for example, that Cennic is a knight with certain privileges, and that if you look at Clogrotto on the map, with all of the resources we gather from there, he is in charge of it. Sir Cennic can play a very good role as a knight by directing his villeins to gather those resources well, and outfitting himself for battle and winning for us. If he has style, he might also do a little "acting" on top of that to make himself more "knightly", but it is secondary and unnecessary overall.
That same style is in place today. I was awarded with the status of 'Baronet', which means I demonstrated skill and dedication in keeping various responsibilities and assets organized for the Duchy of Wessex. It also means that anyone in the guild, or outside the guild for that matter, can come to me as a leader in the guild. If a decision needs to be made it is expected that I will make it
and that I will own it.
You will seldom see me RP in local chat though, and you will never hear me RP in TeamSpeak. That's not my forte. In fact, half the time I screw up trying to RP in 'formal' communications. I work at it, but at the end of the day its about getting the job done so that as a guild, we can maximize our fun time in the games we play.