John Walter, over at Machina Memorialis figures out from the trailers the most significant plot change in the Beowulf film:"Keeping in mind, as I argued on ANSAXNET, trailers are often deceptive these days, I think we finally have a trailer that’s revealing exactly how Gaiman and Avery rewrote the story: Grendel’s mother is the dragon."
It's well worth reading the entire post, but the basic idea, which I think is right, is that Grendel's mother is the dragon, Beowulf lies about killing her due to greed for treasure, and also that Beowulf himself is the "thief" who steals the cup from the dragon, setting off the final confrontation. John links this approach up with the story of Fafnir and talks about Tolkien's dramatization of "dragon sickness" (a point developed in other contexts by Shippey). John says that
In other words, if what we’ve got are echoes of Tolkien here, Gaiman (and Avery) reinscribe Germanic mythology/tradition back onto Beowulf through the lens of modern Fantasy (Tolkien) in much the same way as Terry Pratchett and Tom Holt reinscribe the Victorian conception of the Old North back on to itself through the lens of that other major figure in 20th century fantasy, Robert E. Howard.
I think, without having yet seen the film, that this is a reasonable way of approaching what we know of the adaptation. But I would also add that there's another way to look at the adaptation aside from linking it specifically to Gaiman/Pratchett's tendencies, and that is the idea of "tightness" in narrrative.
Because mass-culture films cannot be much long than 2.5 hours, and because having audience members turn to each other and ask "what just happened?" or "Who is this guy?" Hollywood films tend to increase narrative tightness by reducing the numbers of characters and giving these fewer people more plot duties. In Creative Writing pedagogy we always went over the line from Checkhov, that if someone picks up a gun in Act 1, somebody needs to get shot by Act 5. Although there are of course exceptions, film, written as it usually is by committee and created under the watchful eye of a continuity director, is very good at taking loose threads and weaving them more tightly into the story.
This is fine as it goes for film, and such narrative tightness is also evident in a lot of literature as well: it's a cliche of Dickins criticism that you just need to spot the right very minor character in the first two chapters to know how the whole complicated mess of the plot is going to be solved.
What's particularly interesting to me is how different this aesthetic is from medieval epic (particularly Beowulf) and its direct 20th-century descendents (Tolkienian fantasy), and how the film adaptations of Beowulf and The Lord of the Rings really point out this contrast. One of the things I complained about when seeing the Peter Jackson LotR films was how small they made Middle-earth: and I meant that both physically (you can stand on Orthanc and see Caradhras; you can take a quick jaunt from Henneth Annun to Osgiliath and back to Cirith Ungol) and socially (everyone knows who everybody else is even before they've met).
For example, in Tolkien's The Lord of the Rings, Strider and the hobbits are aided by Glorfindel, a powerful elf-lord who is seen at the Council of Elrond and then never really discussed again. In the Ralph Bakshe version of The Fellowship of the Ring, Glorfindel is replaced by Legolas, tightening the narrative in one way (not as many elves). In Jackson's version, the hobbits and Strider are helped by Arwen, thus introducing her into the main narrative and setting up the Aragorn/Arwen love story which is not a main element of Tolkien's story until "Many Partings" (though in hindsight you can figure out bits at the end of "Many Meetings" and with the delivery of the standard to Aragorn).
I think we see this same tightening in the Beowulf movie by making all three monsters closely related and having the action in Geatland be directly motivated by the action in Denmark.
I've already argued as to why the Hollywood film prizes such narrative tightness, but it's just as a big a question as to why medieval epic does not. One answer could be found in John Miles Foley's approach: the audience already knows who all of these characters are, so there's no need in any given instantiation to tie them so tightly together. The entire epic world and its many sub-plots are immanent in the minds of the audience. Therefore to them Beowulf is basically tight already: they know who Unferth, Ingeld, Freawaru and Hrothulf are and how their stories fit together.
Tolkien himself seems to have had a somewhat different view, chalking up at least some inconsistencies (which I will take as lack of tightness, though that is somewhat problematic and would require a much longer argument than I have time for here to really lock it down). In Beowulf and the Critics in which Tolkien writes:
It is extraordinarily difficult, even in a newly invented tale of any length, to avoid minor discrepancies; more so still in re-handling old and oft-told tales. Critics would seem seldom themselves to have experienced the difficulties of narration. The points they fix on in the study, with a copy that can be turned back and forth for reference, are usually such as may easily escape an author, and still more easily an audience. Let us think, say, of Malory, were all his sources lost beyond recall. (B&C 140 n.1)
I think Tolkien started to go even beyond this point, however, but dropped it. If you refer to the Textual Notes for that page, you'll read:
even in a newly invented tale, of any length,
Critics would seem seldom ^themselves to have experienced
beyond recall. I have now ?? ?? ?? ?? in which the heroine's very name changed from Edith to Ethel 170.
You can see why a change from Edith to Ethel would have jumped out at him. I wonder if there would ever be a way to track down what book he was reading that did this (there's a similar minor inconsistency in Susan Cooper's The Dark is Rising).
I extrapolate from these quotes and from other things Tolkien wrote to suggest that he recognized--though not naming it--that the work of the critic in the study who can flip back and forth between different texts is fundamentally different from that of the storyteller who has to compose in real time or even who is writing a long tale. To use Ong's terminology, there is a different noetic at play in each case, just as Hollywood films and medieval epics operate under different noetic conventions.
But in writing his works, even though they were conceived in the study where an author can turn back and forth for reference, Tolkien adopted the style -- i.e., the narrative slack -- of the medieval epic. The "Great Chain of Reading" that Gergely Nagy discusses is part of this style, but there is also Tolkien's willingness to introduce entirely new characters -- Gildor, Glorfindel, Farmer Maggot, Erkenbrand, Elfhelm, Quickbeam--and not always tie them neatly into the final action the way they would all have to wrap up neatly in a Dickens novel or a Hollywood film. Narrative slackness is a big part of the aesthetic effect of both Beowulf and The Lord of the Rings (my favorite part in Beowulf being: "Oh, never bothered to mention the second monster until now that she's attacked the hall, stolen the arm and killed Æschere--oops").
I would submit that one of the great gulfs between those who get aesthetic pleasure from Beowulf and LotR in their original forms and those who prefer the film adaptations is likely to be the degree to which the aesthetic of narrative tightness has been internalized. And it's really important, as I keep telling my students, to keep remembering that modernist aesthetics are not universal (i.e., there's no outside standard that proves that "tight" writing is good and "slack" is bad) but matters of habit, preference and tradition.