There's a conversation going on over the Comix Scholars listserv about comics as representations of history, either old history or present history. It started with Spider-man #36, in which Spidey witnesses and comments on 9/11 and expresses his frustration that the supposed superheroes couldn't prevent it, despite having prevented many such disasters and attacks in the past. This was quickly compared to Speigelman's In the Shadow of No Towers, an autobiographical account of Spiegelman's experience as, essentially, just another New Yorker, trying to survive and sort out what the hell was going on. I, in my way, tossed a couple of monkey wrenches into the conversation in response to two assertions: first, that in history, as soon as there is a narrative, there is also a narrator, and second, that the two comics are obviously different, and of different levels of quality.
I'm not sure that there is a narrator as soon as there's a narrative. This may sound a bit literal, but it seems to me that in visual media, there is not a narrator in the traditional sense of a story "teller." There is instead a story "shower" (one who shows, not water falling from a height), and as some of you might have noticed, I'm not one to equate telling and showing without a heavy dose of caveats.
I think there is a distinct difference between the voice of a narrator, reproduced by either print or recording, and the less personified entity and/or set of representations that is a comic book or a film (and for argument's sake, let's talk about comics/films that don't have words).
The narrator voice is, traditionally, a singular presence that we can trace back to a speaker. Even "voice of god" narration is associated with one speaker. There are, of course, many ways to upset that traditional sense of narration (e.g., using multiple narrators or a narrator voice that seems to slide from objective to subjective, or one that is aware that it is a narrator, etc.), but by default, the language-based narrator is one speaker.
In visual narrative, the presentation of many pictures does not immediately imply a original, anthropomorphic source. Yes, of course, we tend to know who drew our comics. Yes, of course, we tend to know who directed our films. But that is a product of a set of paratexts, of an art culture that is still preoccupied with the auteur, the singular "voice" behind the "text," even if there is no literal voice (spoken language) or a literal text (printed words). As such, I'd argue that that auteur presence is lessened.
Now, of course, we have several decades of literary-critical tradition telling us that it's all "text," and from that perspective, it's perfectly legitimate to say that anything that presents a narrative by definition involves narrating. I do understand that line of reasoning, but equating language-based narration with visual narration elides the operative differences between the two, of which there are many.
The real question in the present discussion, then, is how the implied presence of a creator behind a narrative might change from a language-based history, to an image-based history, or to one that is a combination of the two. I think it's probably fair to say that viewers tend to be less critical of images because they seem more transparent, more of a mimetic representation of reality (whatever the heck that is). Think about how much more sensational a picture of present-day Iraq or New Orleans is than a block of text, for example. The image seems to travel through a viewer's senses with less conscious filtration. In print, however (despite how logocentric our culture is), we at least have the sense of a single speaker with whom we might disagree. I suppose my point, eventually, is that the rhetoric of visual narrative is very different than the rhetoric of language narrative.
As for the two examples, Shadow of No Towers and Spider-man #36, I don't know how useful it is to talk about a difference in quality. When I have my lit-crit hat on, I'm not sure how to even answer that question in a way that isn't immediately presumptuous or even classist. I don't say that to imply an accusation, of course, but to suggest another way to address the very important problem Pedro brought up. I think we can learn a lot about these two comics by identifying the different levels of complexity in the narrative construction and the rhetoric, as well as the target audience/context of reception.
Shadow was originally published in a newspaper, arguably the ancestral home of comics in America, and then assembled into a coffee-table book (which is to say, a book so big you could serve coffee on it). Joking aside, my point is that the conditions of its publication indicate that it was originally aimed at casual newspaper readers in New York [I later found out this is not entirely true], so it was local but the audience was assumed to have a certain broadness to it. It is a biographical story, in large part, so the audience is assumed to have some knowledge of who Art Spiegelman is, which is a fair assumption, given his fame and his previous gig drawing covers for the New Yorker. The conclusions, if we can even call them that, to which Shadow comes are ambiguous, morally grey, and very contingent, leaving decision-making in the reader's hands and revealing just how complex those decisions are, especially in the choice to almost imperceptibly transition from Spiegelman's narrative over to reproductions of old comics. His multi-threaded pages (which use both sequence and series, in Groensteen's terms), and his slip from his own story to reproductions of old comics forces a more critical perspective of the very notion of history, and de-emphasises the personal nature of the story, which is very autobigraphical. That said, the complexity of the narrative presentation also filters out those who don't know or don't care to navigate a complex comics page.
Spider-man #36 is a much simpler narrative construction, so it is theoretically more approachable to a viewer who isn't accustomed to comics. It proceeds linear/chronologically; there is only one narrative thread per page, as opposed to the three or four on Spiegelman's pages; and it has continuous, textual narrator voice, which anchors the story to one point of view. The ultimate theme or 'moral' of the story is also fairly unambiguous. It is a story of mourning, without much attention paid to the historical context of the event. It also brings cold, hard reality into a high-fantasy setting, which DC was not quite willing to do (although I'd argue that a lot of the current angst, violence, and moral ambiguity of DC's comics is a reaction to living in the "post-9/11" world). That said, American superhero/mainstream comics are read by a small, and possibly even decreasing, number of people and the almost impenetrable continuity of the Marvel 'universe' wards off a truly general readership, and limits the content to a small, dedicated audience, so while it is structurally more simple to read, its publishing context makes it less accessible.
Off the top of my head, those seem to be the operative differences between the two, as opposed to simply calling one more profound or higher quality than the other.