Okay, here are my two cents on Zod in The Man of Steel (It's not called Man of Steel, right? I'd prefer to add the "The" and even Superman to the title).
When news broke out that Zod was official; it caught me by surprise because, like many, I thought Brainiac was going to be in the film. I still go back to the first news of this reboot that mentioned Luthor/Brainiac. But after I thought about it, I realized something: Zod is still a great idea that many people are either not thinking of or overlooking.
 
Because they are looking at the comics as the source material for this film (unlike the others), anytime I think of Zod, its either not just or never-ever, Stamp's version, it's the comics, and there are good reasons. The recent comics, even including Byrne's reboot, have featured great stories or moments of General Zod that I think about the most than Stamp's version: Byrne's Pocket Universe Zod, I never read Our Worlds at War but there's that version of Zod (known as Russian Zod), For Tomorrow's Zod; and there is the current Zod by Geoff Johns, to which, yeah, he is based partly on Donner's version, but he is his own character that the notion of that isn't on your mind. And that version of Zod, in stories like Last Son and New Krypton, were either great or had good moments. Plus, in terms of other media, if we look at the recent stuff from Smallville such as Season 9, that version of Zod was pretty cool too. And no one thought about Stamp's version, except for the line "Kneel before Zod". With that in mind, even though he is an old villain being used, it's not bad because of all of these show what a great character he is.
 
Plus, another factor that I have to bring up is that this isn't Synder's film, it's mainly Nolan and Goyer's Superman film that Synder is directing. It's his ideas that glued with their ideas that led to Synder being hired for the job. Now, I'm not bringing Nolan up because of his track record; because we're talking about villains, Nolan and Goyer can juggle villains than it seems no else can. Look at their Batman films; Batman Begins had seven villains, Dark Knight had three, and Dark Knight Rises seems to be going from 3-4 villains but there might be more. Different from the previous film series where the villains took over those films, right? So, the reason why I'm bringing this up is because, well, Zod may not be the only villain, right? 
 
It seems painfully obvious that Lex Luthor will be in the film, but what-if there is a third or fourth villain that is goign to be in this film? Synder made a joke saying "there might be a character that people would call Superman", people said he was joking but then again he said Zod was just a rumor, right? What-if he wasn't? What-if that mention of what might be Bizarro really means Bizarro is going to be in the film? And, again from that first article on this film, what-if Brainiac is going to be in the film like the Zod/Brainiac team-up we saw in Smallville? What-if its a mixture of old and new villains for the reboot? Yeah I know, this is all speculation, but with all of this factors behind this film which is all different than before, and for good reason, I don't think they would have just Zod or Zod and Luthor without having someone else to balance it all out. Zod/Luthor? Zod/Brainiac? Luthor/Zod/Brainiac? Luthor/Zod/Brainiac/Bizarro? Speculation, yes, but man I know it can't be just one villain.
 
Now with what we know about the story thus far; set in the early years featuring a young Superman, a film that makes Superman relevant today. Nolan quoted as saying that the film had a story he "never seen before that makes it incredibly exciting. I wanted to get Emma and I involved in shepherding the project right away and getting it to the studio and getting it going in an exciting way. A lot of people have approached Superman in a lot of different ways. I only know the way that has worked for us that’s what I know how to do." And added that while he "admired Singer's work on Superman Returns for its connection to Richard Donner's version, but stated that the new film would not have any relationship with the previous film series." Snyder directing, with Nolan having creative input. And of course there's DCE and them knowing how burnt we've been; if I'm wrong and its just Zod or Zod and Luthor; just because Brainiac isn't in it won't make it a bad movie. In fact, it might as well fit the storyline more. I remember alot of people thinking "Birthright" with this film, and with Zod in it, I thought about the scene from that book with the Kryptonian warships and Superman battling them from the ground to the skies and back in Metropolis. On film, wouldn't that be sweet? Nothing is set in stone yet, but if it is just Zod, with the scale Synder can pull off, and a story Nolan and Goyer can pull off; we're still in for a real treat coming in 2012.
 
I'm not against Zod in it.