After my encounter with this hastily put together guild.
1. No real background knowledge seamed to have be researched, as they were claiming Gregori owned it when they first entered the game.
2. They clam to be enhancing roleplay, yet for 1 hour until they were told to stop, 75% of say was [ooc]
3. I have seen it claimed no one will be told to leave. quote from a member of this guild. "If you want to leave, feel free to do so"
4. I was also Harassed in tells, also they Harassed me by luring monster away with magic, to stop me fighting it.
5. But the biggest sin of all was on #planeshift, I was accused of being rude in tells.
SO to sum up, if you want this, do not force it on others. Also do not harass anyone in away.
First it's important to note that you can't make something work well without experience. Not unless you're extremely lucky. I'll try to give my opinions based on Janner's account of things.
1- In the Promotional Thread topic it seems there is a good background knowledge. Donari has read the book and obviously contacted Gregori. She may have failed in either expressing that knowledge or in communicating it to her staff. If so... She should think about organizing things better.
I considered the other points as rather irrelevant since they do not concern the guild directly, instead focusing on the interaction between players. This should be handled by GM's, not discussed in the Guild Forum.
As a side note, Janner considers "The Hydlaa's Arena" isn't owned by Gregori and the guild's official vibe automatically sounded defying to him. That's what I meant about conservative players.
He's a GM and he should know what is acceptable... I haven't seen him take much notice of any other guild though and there are ones with graver assumptions.
However I would comprehend the frustration of someone else that planned to make a similar guild and be met with less sympathy. I am guessing that in this circumstance players would lean over choosing Donari's Guild because it assumes an official status. That would be a very unfair situation.
I don't think so .. someone else planning a similar guild will be met with less sympathy because they're not the first to do so and can be accused of simply copying Donari's recipy (regardless of whether they did or not). Obviously they can assume an equally official status and also say they work with Gregori, applying his rules to the Arena. That means they'll be practically the same as this guild though.
I would chose Donari's guild because it is original and the first of it's kind .. unless the new guild has a better concept of course. 
What Donari intends by claiming they work under Gregori is exactly the same as what I intended by claiming Dakkru's Will works under Oriven, Rulayne and Londris. It means these guilds will abide by the material settings already gave us, create extra content beyond it to a degree but each time that new settings material comes up they'll re-evaluate the way they work. Saying Gregori is in charge is in many ways the same as saying Settings is in charge. Settings brought out a book, under Gregori's name of how the Arena should work. This guild is simply meant to turn said book into practice.
And should a guild with the same job pop up .. well, UtM already said it, just like when you have two different people bartending the same tavern .. both will have to decide whether they'll work together or fight eachother for customers.
A good point. Specially if Donari doesn't complain about having other people sharing that "official" status. I'm still not seeing her happy if someone takes up that task for itself and starts acting like a complete corrupt/clown while assuming to be Gregori's staff.
That is why I keep my conservative thinking: assuming official status is a responsibility that should be handed by the corresponding authority within PlaneShift.
Again, I agree wholeheartedly that Donari is doing what should have been done a while ago, either by a player project (maybe one less ambitious as far as demanding official status is concerned) or by the respective part of the PlaneShift team. I'd rather have Donari claiming full official status than have no one tending to the Arena.
EDITED: Erased a part and added another, to reflect what Donari said.
EDITED x2: Considered point 2 irrelevant as well.
Moderator's Note: I think Janner and Donari have discussed enough about their encounter. Further conversation concerning that topic and failing to provide useful opinions to the guild will be deleted.