Aran are comeing soon?!

I mean just use your brain and think. They will definitely do some promotion and advertising before the launch of Aran. They will tell you 1 or 2 months in advance. Therefore, GMS will definitely not be getting Aran in December. Instead there are chances that GMS will be getting it in Jan or Feb 2010.

...
Explain the quests that were added to GMS data then, such as

 Spoiler

 They're Coming Back!

NOT COMPLETED:
Cassandra, looking into her Crystal Ball, says they will soon return… But who are 'they'? For details, let's go see Cassandra.

IN PROGRESS:
Cassandra said you'll find answers if you look into the Crystal Ball.

COMPLETED:
What you saw in the Crystal Ball was the revival of the Arans. The Arans… Don't you want to know more about them?

 The Revival of the Arans

NOT COMPLETED:
The Arans! They are going to revive. But who are the Arans? And why did they disappear from Maple World? Talk to Cassandra if you'd like to find out more about them.

IN PROGRESS:
Cassandra seems to know a lot about them...

COMPLETED:
The 12 Aran Memory Fragments? Perhaps you should go see Cassandra to find the Aran Memory Fragments.

 Vague Aran Memories

NOT COMPLETED:
If you're curious about the Arans, talk to Cassandra.

IN PROGRESS:
She says you must collect Vague Aran Memories in order to obtain an Aran Memory Fragment.

COMPLETED:
You have collected an Aran Memory Fragment. Cassandra told you a story about a girl who's waiting for the heroes in Rien. What was her name…? Li… Lilin?

 Cassandra's Album

NOT COMPLETED:
Cassandra says something extremely bad has happened!

IN PROGRESS:
Cassandra says she's lost her album and suspects it has something to do with Gaga's artifacts. Hm, but you're busy collecting the Aran Memory Fragments. Perhaps that can wait until after you're done helping Cassandra, who seems desperate. If you collect artifacts, you may naturally find Cassandra's Album.

COMPLETED:
You have acquired an Aran Memory Fragment for returning Cassandra's Album.

 Dim Aran Memories

NOT COMPLETED:
Go over to Cassandra if you're curious about the Arans.

IN PROGRESS:
She says you must collect Dim Aran Memories if you wish to find out more about the Arans.

COMPLETED:
You have finished collecting an Aran Memory Fragment. What happens when you collect all 12?

 Signs of Their Revival

NOT COMPLETED:
There have been subtle signs that indicate the revival of the Arans. Talk to Cassandra for details.

IN PROGRESS:
Ice Shards from the ice the Arans were sealed in have been found near town. Where are those Ice Shards?

COMPLETED:
The Aran Memory Fragments… How long will it take for you to collect all 12?

 Faint Aran Memories

NOT COMPLETED:
Many have begun to forget the Arans… But if you're still gung-ho about finding their Memory Fragments, go talk to Cassandra.

IN PROGRESS:
Cassandra says you must collect Faint Aran Memories.

COMPLETED:
You seem to have collected about half of what's required.

 Wolves Waiting for their Masters

NOT COMPLETED:
You must first go see Cassandra in order to collect an Aran Memory Fragment.

IN PROGRESS:
You must look for the wolves that are waiting for their masters.

COMPLETED:
When you approached the wolf, it jumped up and left an Aran Memory Fragment.

 Cloudy Aran Memories

NOT COMPLETED:
Let's go talk to Cassandra and ask her about the Aran Memory Fragments.

IN PROGRESS:
Let's collect Cloudy Aran Memories.

COMPLETED:
You have collected an Aran Memory Fragment.

 Preparing for Their Arrival

NOT COMPLETED:
Cassandra says she needs your help.

IN PROGRESS:
Cassandra has asked you to bring a weapon from the town Weapons Shop for the heroes who will be reviving soon.

COMPLETED:
The weapon you brought will be used by the legendary Arans. Isn't that exciting?

 Lingering Aran Memories

NOT COMPLETED:
You don't have enough memories of the Arans. You better go see Cassandra.

IN PROGRESS:
Let's search for Lingering Aran Memories.

COMPLETED:
You have collected an Aran Memory Fragment.

 The Memory of the Heroes

NOT COMPLETED:
You're getting close to collecting the 12 Memory Fragments Cassandra mentioned, but you're not quite there yet. Let's go back to Cassandra.

IN PROGRESS:
What the… She was talking as if she were going to give you an Aran Memory Fragment but… Hmpf, it's annoying, yes, but what else can you do? Let's talk to Cassandra and see what she has to say.

COMPLETED:
You're close to collecting all 12 Aran Memory Fragments. But what are these…?

 Flickering Aran Memories

NOT COMPLETED:
Of the 12 Aran Memory Fragments that Cassandra mentioned, you just need one more! And as you may have guessed, you must go see Cassandra to find the last memory.

IN PROGRESS:
Let's collect Flickering Aran Memories.

COMPLETED:
Finally! You've finished collecting all 12 Aran Memory Fragments. But what are all these memories anyway?

 The Hidden Meaning Behind the Memory Fragments

NOT COMPLETED:
You have collected 12 Aran Memory Fragments. But they seem meaningless… What is the logic behind this? Cassandra probably knows the answer to the mystery.

IN PROGRESS:
Hm? What? Huh? Each fragment has its place? Switch the order of the fragments around.

COMPLETED:
July 9th, 2007. Will the Arans really revive?

Quest that are added in the data doesn't mean it will be release. And most MapleStory Servers have data kept inside their WZ file for years but never release. An example in the Taiwan Map (Night Market/Ximending) in MapleSEA. For the past 2 years, the added the data but never release it. Many maplers have accidentally teleported there after their fishing rod expire via Orbis. Recently, the same thing happen again.

The data like Aran are added now so as to minimize the file size of the patch when it comes to the official launch of Aran.