So, Cyborg is in the Justice League now. Lots of people know him from the Teen Titans animated series, though not enough people care about him for a redesign/repositioning for him to cause any real fanrage. I'd like to discuss some of his potential, not only as a JL member, but as a standalone character as well.
He is most well-known for his iconic
Mega Buster Sonic Cannon, though he has other abilities too. Lasers, grappling hooks, shockers, a bunch of techie weapons. In some appearances he can even detach his arm, and control it's actions from a distance. He seems to be a decent enough H2H fighter too, as shown here, here, and here, where he beats down both Ravager and Kid Devil with relative ease. Lots of people are saying he'll just be the tech/computer guy, yet I feel like DC is trying to portray him as a 'frontline fighter', as seen in Justice League Dark #1, where he appeared alongside Superman and Wonder Woman to fight off an unidentified threat. Anyone who has seen the JL covers will know that he looks like a freaking tank at the moment, at the very least he looks like some who could take a hit and give one back. No doubt he will be a techie character though, atleast to some extent. I'm sure there'll be tons of hacking sub-plots and the like that Cyborg will be utilised in. People are saying he'll be JL's Iron Man, which makes sense I suppose. In my opinion, he shouldn't be portrayed as someone with gadgets, but someone with near full-on cyberpathy, something which I think hasn't really been seen in the JL before. One possible danger with this is that writers might simply use him as a high-tech swiss army knife, inventing whatever ability would be useful in the current scenario as an 'easy way out'.
Role as a Justice League member:
Some people are saying that Batman is a sufficient enough techguy for the JL, and Cyborg can't really bring much to the team. There is a bit of role-clashing there, though I think this'd be a great chance for Batman to become a more focused detective archtype - this very aspect seems to be what many of his fans seem to love the most about him. They could both fill the roles of the tech expert when needed, though I feel Cyborg will be taking on a lot of it for now. Also, I'm biased here, in that I'd like it if Batman wasn't everywhere all the time, as he seems to be these days. I've already stated how I think Cyborg could ending up alongside the likes of Supes and WW, and I think Cyborg could fill a unique niche as someone who could manipulate/take advantage of technology found out on the battlefield. There are a lot of possibilities with that, enough to defend his spot on the JL at the very least.
Strength as a standalone character:
Understandably, he doesn't have an ongoing of his own, though I'm surprised he doesn't have a mini yet. He's had a fair number of appearances in comics, though a lot seem to be just background roles. One potentially interesting plot element is...his face. He pretty much can't have a secret/cover-up identity like the other JL members can, can he? I mean, put Aquaman and WW in some normal clothing and you wouldn't even know they are heroes. Martian Manhunter had shape-shifting abilities too. So does that mean he is publicly 'on duty' 24/7? It's a notable distinction from everyone else, at the very least. He doesn't have much of supporting cast, outside of Element Woman, who was confirmed to be appearing in JL eventually. She seems like a fun character in her own right, hopefully they'll retain some semblance of the interactions they had in Flashpoint. Regarding his rogue gallery...well, outside Teen Titan enemies, I found two groups, the Phantom Limbs and the Cyborg Revenge Squad, though they seem quite boring. If they want to capitalize on the fans of the animated series, they should bring in some of the villains from that (perhaps this'd be a good time to bring back Brain, Monsieur Mallah, and the rest of the old Legion of Doom?) In the DCnU he is based in Detroit, the only notable DC character I can think of that's currently there too is Firestorm (I think), so they could easily think up a bunch of new villains for him, if they wanted to.
I think that if DC wants fans to accept Cyborg as a convincing and deserving member of the JL, he'll need some work put into him first. He is a well-known character with enough potential for some fun stories, so seeing how he turns out in the DCnU will definitely be interesting.