I'm glad that Jackson omitted the Bombadil episode. Somehow it seems to me that to do that right would require genius. I think Jackson's a very skilled craftsman, but not a genius.
Some years ago I read Coventry Patmore's brief essay "The Point of Restin Art," which is available here:
Principle in art, etc. : Patmore, Coventry Kersey Dighton, 1823-1896 : Free Download & Streaming : Internet Archive
That gave me the key to Bombadil, which I wrote about in a short paper that will (re)appear in
J. R. R. Tolkien: Studies in Reception eventually. In brief, Patmore noticed that great works of art often have a "point of indifference" in the composition, to which the eye returns after looking at other details. He instances the Infant's heel in a painting of the Madonna and Child. Patmore invites the viewer to imagine that point gone and to perceive how much less well the art would "work" as a while. He gives an example from literature, of a character in
King Lear who is not particularly interesting in himself in contrast to the other characters. I applied this principle to Tolkien. Bombadil is the character who puts on the Ring
and nothing happens. He takes no part in the War of the Ring. If we liken the episodes and characters of
LotR to a vast canvas, the Bombadil material could well be the "point of rest" that's so mysteriously important.
I think Jackson's movies could help some people to test this idea. It could be that, if you come to the book having been immersed in the movies, you come acclimated to a protracted swirl of adventures. That's what you may want from the book. When you read the book, it may seem to be unsatisfactory because the adventures occur against a carefully evoked context of the natural world, of ordinary social life, of contemplation of beauty and the depth of time, etc. Bombadil's world is part of this, as is that which we glimpse in Sam's song in the tower with "above all shadows rides the Sun, and stars forever dwell," etc.
Also, as I wrote in another paper that will also be reprinted in the book,
LotR celebrates the Four Loves.
Touchstone Archives: Rings of Love
The Bombadil material gives us what we wouldn't have, otherwise, in the book, namely a picture of newlywed love. It doesn't matter that Tom and Goldberry have, perhaps, been together "always"; Tom is always in the state of a young man who has just married his lady. Tolkien was writing in a time and place in which it was normal for a couple not to have sex or cohabit till they were married. The honeymoon was the period of newlywed joy, lasting weeks or months, where now "honeymoon" is, I suppose, the term for the expensive vacation taken by just-married couples whose sexual coming-together is long behind them, so that things would feel rather flat after their wedding if they didn't do something financially extravagant.