I'd say another GTA installment would be something people would clamor for. No idea if people have been begging for it, but it's certainly been long enough since the last installment (2008) for a sequel to be announced. Though, the Rockstar guys do have a history of doing big announcements. I'd think we'd see them at something like the VGAs or E3 before we'd see them on the cover of Game Informer.
To me, it's fairly clear just based on how people tend to answer questions. If I asked you that question, your answer of "nope" would only be clear if you were answering the first portion - if you were trying to address the second portion, you'd have to elaborate to clarify for the other party. For example:
- Andrew_Reiner Is the next cover a game that was already revealed or not?
- Andrew_Reiner: @MrTissueBox Nope, it has! (note, this is not what he http://twitter.com/#!/Andrew_Reiner/status/12710489284939776)
Even then, it's kind of a strange way to respond. It reads uncomfortably. Most people wouldn't respond that way, especially an editor for a print magazine.
Yeah, having tried out a bunch of other similar question-answer responses in my head, I think I agree that Reiner means to deny the first distjunct. It seems the pattern is something like this. Suppose A asks "Are you going to eat that cake, or not?". If B were to respond negatively, it seems most natural to say something like "No, I'm not", to convey that B isn't going to eat the cake (so denying the first disjunct). If B were to respond positively, it seems most natural to say something like "Yes, I am", to convey that B is going to eat the cake (and, again, targeting the first disjunct). It seems more awkward for B to convey that she's going to eat the cake by saying "No, I am", (she's denying that it's not the case that she'll eat the cake). Similarly, it seems awkward for B to convey that she's not going to eat the cake by saying "Yes, I'm not". That is, it's more natural to use "yes" or "no" to target the first disjunct, rather than the second. But anyway, the upshot is that I agree with your assessment that it would have been infelicitous for him to reply with "Nope, it has" - if he wanted to say that the cover was of a game already revealed, we might expect him to have said "Yes, it has".
(I still find Reiner's response conversationally infelicitous, because I still find it somewhat unclear as to what he's denying. I need to do a bit of reconstruction to work out what he means.)