It's not so important the sequel be darker or edgier, just simply better. Martin Campbell has proven with Casino Royale, that he knows how to do direct a fantastic film. The actors proved to have taken their roles seriously. The story of the film, however, was very weak and ultimately the core reason for its lack of success. If any direction needs any change at all, it rests not in the director or the actors, just simply in the story.

My only worry is WB. Good or bad they screw up everything.

You pretty much answered your own wonderings here. He convinces them all no fear blah blah then Sinestro puts the ring on. The Yellow Power Ring represents all that is bad and by putting it on they're telling us Sinestro has changed and isn't the great and powerful Green Lantern we all thought. That's how how took it anyways. It was a 6 second clip so there is no telling what it was supposed to mean. Could be way in the future for all we know.   " Lucyyyy, you got sum esplainin' t'dooo!"  She just wants to be in the show =D

Did Ryan Reynolds indirectly talk about Green Lantern and even possibly saying it sucked?
 
Audio: http://thepiratebay.org/torrent/6581258/Opie_and_Anthony-08-03-2011_After_Show

While promoting his new upcoming movie "Change-Up" (which is now currently getting hammered with negative reviews at 26% right now just like GL), Ryan Reynolds, not directly naming the movie in question, talked about how studios are freaking out about their film bombing in the box office because word of mouth these days can actually destroy a whole movie (this gives light to the explanation of the movie reviews embargo placed by WB on Green Lantern, plus it was the only non-independent film in his resume which featured him as the main start that bombed).

Ryan Reynolds: "The studios can't trick you now into going to see a bad movie, and still expect to make their budget back in one weekend. Because on Friday night people will come out, and if the movie sucks they're gonna go on Twitter and Facebook telling everyone they know that the movie sucked." 

I thought the GL movie was pretty entertaining, however I haven't read any GL series. So as one who hasn't read the GL, I enjoyed it. I thought it was a good start, but I do think it would be better for a sequel to be a little more dark and serious. I didn't realize this movie did that poorly though, I thought it was pretty big.

There!....again throwing those silly words... "Darker"..."Edgier"...
As if it meant anything, coming from Hollywood producers...

Comic book fans are likely more interested in hearing about two upcoming Ryan Reynolds-centric projects: Green Lantern 2 and Deadpool. According to the actor, he’s still hopeful about getting to play Wade Wilson onscreen (again), but doesn’t know yet whether he’ll be donning CGI green duds as Hal Jordan for a second time.

Next on the agenda for Reynolds is the Dark Horse comic book adaptation, R.I.P.D. Afterwards, he may be teaming up with visual effects artist-turned-director Tim Miller on Deadpool, which was a character Reynolds had read and been a fan of since the 90's. The upcoming film will be a “total reboot” of the title character, following his appearance in X-Men Origins: Wolverine.

Reynolds told MTV that the Deadpool movie is still “in development,” but that he doesn’t expect to have to choose between starring in that or the R.I.P.D. adaptation. Even if that were the case, it’s pretty obvious which flick most fans would want Reynolds to move forward with (Hint: It’s not the one with undead cops and evil Kevin Bacon, as much fun as that sounds).

Zombieland duo Rhett Reese and Paul Wernick are scripting the Deadpool movie, which is expected to retain the same elements (4th wall-breaking humor, graphic violence, etc.) that have earned the anti-hero a strong following from comic book readers. Miller is an untested talent in the area of directing, but his technical expertise should ensure that Deadpool will at least look and sound up to scratch.

Despite recent word from Warner Bros. studio heads about a possible darker and edgier Green Lantern 2 in development, Reynolds isn’t so sure he’ll be reprising his turn as daredevil test pilot-turned-intergalactic defender of justice, Hal Jordan, in the followup.

“I have no idea, that’s not up to me. I don’t write those checks. And if I did I certainly wouldn’t be standing on a red carpet, I would be sunning myself somewhere."

Speaking to where we might find Reynolds' Green Lantern in future film installments, the actor didn't have quite as much to say now, as he did back before the film's release (read June 10 article here).

"There are infinite [possibilities for a sequel]," Reynolds said. "70 years of history there, you could go anywhere."

Arguably, though, the problems with the Hal Jordan character in Green Lantern had less to do with how Reynolds played him and more with how he was (poorly) written. So long as the screenplay for the sequel does a much-improved job of encompassing the Lantern mythology (among other things) there’s no reason why Reynolds shouldn’t be brought back.

A mid-credits scene in Green Lantern set the stage for a sequel that revolves around Sinestro (Mark Strong), but it’s possible the next Lantern pic will ignore that plot thread – and end up being a partial franchise reboot, along the lines of next year’s Ghost Rider 2. Heck, for all we know at this point, it could even end up featuring one of the other human Green Lanterns​ (like Alan Scott or Kyle Rayner​) as its protagonist!

The tone of the movie was fine, they just need to get a great script.
And I don't know how they screwed up, I've read onee of the ealy drafts of the script, and it was 10x better than the movie. Probably because they stupidly tried to include Parallax, made Hector whiney about his dad, and didn't give enough time on Oa.

Why are they still talking about this? I mean, it was funny for a bit, but I'm starting to think they actually mean it. Which would be silly, because nobody is in the business of throwing money away, and when you go "darker, edgier" about something it's semi-ironic code for "we don't know what the hell went wrong".

What drugs were they on when they approved a $300 million production/marketing budget? The only way they could have possibly justified that is if Will Smith played the main character.

i think a sequel would be awesome. the first was good but not great. only thing they would need to do to make it better would be make it darker and/or maybe edgier.

it should have been John or Kyle

I just wish they had actually made a sequel...

Dark and edgier isn't the answer to making a good GL movie. If anything it should be bright.
They need a better story overall, greater organization, and engaging villains.