Wow okay, I've not read everything that all of you have posted but my opinion however was requested for this thread so here goes a small response on the initial post and idea, just some of my thoughts on the issue, nothing anyone has to follow but I do agree over all a general guide is helpful and needed.
IC/OOC chatting (tabs, OOC chat, correct typing, etc.)I use main tab for main ALWAYS unless I use []. Tells.. hmm tells are a bit more tricky, I tend to think for the most part OOC unless whispering, sending a groffle note or whatever. but I've known some that have tired to get me to RP in tells and I just simple told them that hey, I am sorry you char just passed out on oja road..but I am on my way to BD..not much I can do from here maybe you want to get someone closer to involve into your RP, or wait for me to arrive to continue. But at the same time I've used tells to hint to others where I am or what I am doing such as "Izzabella sits alone by the fountain reading a book" and I'll get replies like "so and so wanders around the plaza hoping to run into Izzabella" or whatever sure its kinda OOC but kinda a silly OOC way to let us know IC where we are at so that we can 'bump' into one another. or so we know what we are doing, "so and so is slaying ulbers and trying to stay alive in the process'. I guess for me for the most part unless I know the person well and know that the tell talk is OOC I use [] to make sure its clear.
Auction Tab--- oh thats a touchy tab for me..hehe I'd like for it to be more IC and I try but I admit I'm not very good at that.. I mean for me it goes kinda OOC when you say /tell whoever and then the conversation and offerings go to /tells even tho you can be to far apart to be 'whispering' or whatever but being more IC is something that I'd really like to challenge myself personally to be more IC when I use this tab.
Guild chat I guess its more up to the individual guilds for that..I know any guilds I've been in however seem to be pretty much OOC and at times --but I am not saying we don't RP and have fun and act like our char's in guild chat ever..we just don't regard that and use it in our actual RP--if we did..Izzy and Org would have had WAY more fights!

NPC tab-- ehh until lately I've also used this as more of an OOC tab..I mean its not like other chars near by could hear the convo..and I guess for the most part I took most quests to be more OOC stuff to do in my spare time not really took it into part of my RP, however lately I've been trying to RP them a lot more and only do things that my char would actually do, I improve every day!

Help tab-OOC however I do try to encourage people asking for help to RP all the time

Group tab--that depends on the group leader more or less when you join or make the group thats usually decided then other wise when I join a group the first thing I ask is" [ic or ooc?]" just so that I am safe and know whats going on. I will use group for private planing conversations or whatever if I don't want anyone else hearing and I do by in main I say something about lowering my voice. I also use groups if I got into a 'building" (one thats RP'ed not really entered) because in theory no one outside around could hear.
System tab..OOC

I think thats all the tabs.. can't think right now I am so sleepy.. I'll edit if I forgot one but I Think thats all..
How to respect other charactersThis is a big one for me and we actually just had a small argument on this topic on our guild forums which I seemed to have ended rather quickly

One thing to remember is EVERYONE role plays in their own way, we all know and have been taught diffrent things, we are diffrent ages and come from diffrent places. And some just don't know. I personally have never had to use the /ignore feature (don't get any ideas on bugging me, Velh) I am a very patient person and I am constantly giving second and tenth chances to people, I realize that people have bad days, and make mistakes, I know I have many times. I think in order to respect someones char you have to respect the person playing the char as well and realize that they won't play just like you and you have to adapt yourself to them at times you can't expect everyone to RP like you do and change for you, and if you find that you can't find a happy medium between you and another player then you need to politely tell them that you don't think RPing with them is a working out well, if nothing else just say that your char does not fit well IC with the other persons char..I dunno :/ Also you need to remember that just because the char does something mean or bad to your char does NOT mean they are a bad person IRL or mean or whatever, they just do as their char would do, I have several characters and its always fun because I have some that get along great with certain others and then my other chars are greatly hated by that same char, but OOC we are friends, I've even made some great friends OOC that IC my char hates (one example is one of my chars hates this other char because she thinks he's just scum and a two-timing jerk

[you know who you are] but because of our IC battles we've actually become great friends OOC and its fun cause I still make fun of him all the time

)
How to respect the settingsAbout role played fightingarg..I am not sure I should go here

I am 1/2 and 1/2 on this one..I mean if you can agree OOC first who will win then *maybe* it will work out I dunno..I've yet to be involved in a non godmoding RP fight, I have the stats and skills to PvP so I just prefer that rather than sitting there all night letting the opponent block all my hits while I let them beat me up and take their hits, I'd rather let them kill me so I can move on
About "complementing the system" where it lacksI am not sure what this question means..

if its lacking..RP it!
About Death and its Role playingehh..I guess it all depends on WHY I died.. and if it was a RP'ed death and such..I mean if I am killing mobs and get killed and it was just be doing some boring PL'ing and such..no I don't rp it.. however if I am with a group and we are hunting and I die..I do RP it, and I RP The death curse as well, I am lucky to be alive Drakuu has pardoned me but cursed me with this evil curse blah blah blah.
How to use information (in the forums, in the website, etc.) & MetagamingI tend to think the forums are OOC. just my opinion and I get annoyed when people say to find out more about my char go to this site or that and to find out about this event read this thread and such..I mean sure the forums are great and nice an helpful but more of an OOC way to let ME know there is something going to happen on a certain day or time
okay I think I am done..this really is not as short as it was supposed to be..and I'd like to comment on Zwenze's post-- I agree..thats totally OOC- some have tired to explain its their char 'disgusted' or whatever..but no. I usually get another char in game to do spy for me or pay off someone in the guild for info

And I'd also like to point out as well that because I do have so many alts and such it does not mean that the info I find on one char I am going to let Izzy use and what not, I do know how to RP and thats why I keep my alts on the low down because too many people think "oh no outlaw' when I am on my alts and they wont have anything to do with them or their guilds or whatever,and thats just crap because Izzy is un-lawful not my other chars
Okay yeah thats about all I have to say for now *yawn* if the kids were not awake I'd go crawl back into bed. so yeah..I hope this makes sense and all I'll look it over again latter, if not just ask me questions