Should they make a completely new storyline? Or should they extend the old plot?

In my opinion a new storyline might be really good, or be a complete fail.
Old plot seems more reliable, but I prefer a new one.

A new one sounds better all the way, I want to see more connections to the Mnemonic Abyss.

Same, I would love to keep the same formula from the first game, but expand on it tenfold.

Add more playable characters, side-stories, ghosts, locations... everything! And implement more side quests like the password keys and Girl in Red.

I guess I'm outvoted. Lol.

A new story would be nice, but there are lots of things in the old story I'd want to hear about. I guess old story elements could make a new story, but I might be more of a "continuation" person. I like sequels, and I like it when characters bring up stuff that happened in the previous storyline.

....I may have voted what I didn't really think...a sequel would be the same people, but different things happening...right? Maybe some of both...if that's possible. A thing I don't like about some games is that apparently the things that happened in the previous game aren't talked about anymore in the sequel.

Bleh...I need to think before I just go with my gut feeling. xD Oh well! That's what this was brought up for! To discuss things.

They could make it a perfect sequel by referring to events happened in Calling, like the characters and stuff.

: D I would really like it that there is a bit of a new story, but everything seems to connect to the old one, and to Reiko. Like, Reiko's spirit has not been completely calmed...

Or better yet, this is maybe a prequel to 'Calling', and it tells the story of other idiots-I mean, characters (xD JK, Makoto and Rin for the win) who get themselves sucked into the Black Page and into the Abyss with Reiko. Heck, maybe the girl in red could actually be a playable character in this one, and we find out her story!

xD Sorry, I must sound nuts...

With another storyline, it's just a look-a-like Calling. You know, diffrent characters, diffrent ghosts, diffrent places.. It's just another copycat.

Calling 2 must have other characters, and maybe some old who helps you out, maybe a few new places -connected to the hospital again-, with some new ghosts, mostly old one -like the school threesome-, and a Reiko return.
Maybe Reiko will help u out in this one. That Sadao is the bad ghost (he killed Makoto, remember).

So..
Calling 2:
-Other characters, maybe old non-playable who helpes you
-A few new places, delete some old (barbershop, hotelroom)
-Some new ghosts with the new places
-Reiko make a return as a good(?) ghost, or maybe a bad one
-Sadao make a return as a bad(?) ghost, or never return, but find his notes

But that are some thing. With the same storyline, you must find out about Reiko again. That's not really fun (if you have played Calling(1).
Only another story, with the points above, will make a good game, I think

If there is a sequel, They BETTER make a role for the Girl in Red

I think they need to make one that mentions, but doesnt directly involve Reiko. It might not make much sense to directly involve her into something sinister, because her problem was pretty much resolved. I would definiately need to involve the Mnemonic Abyss and i would also like a better and more explained role for the Girl In Red, even though the lack of knowledge about her is what made me so curious to find her.

I personally, like the idea of a kind of prequel - preferrably following The Girl in Red. I really want to know who she is and what caused her to enter the Abyss. But there are other options, because after all, the counter showed over 950 people vistied The Black Page, so it's very likley there are even more areas, ghosts, and characters that could be created.

I want a prequel with the Girl in Red. That would be so smexy.

A new storyline would be very nice.
But I would like a continuation of the first game.
I agree with ARMOR15, they need more characters and said quests like the woman in red, the phone keys and the death pictures.

While Calling 2 in general sounds good, I think that there should be a new story. Certainly, Reiko wasn't the only ghost in the Mnemonic Abyss who had unresolved business in the world of the living.