There may be spoilers if you haven't read The Lord of the Rings.
(Note, I'm writing this up without benefit of a printed copy of The Lord of the Rings at hand, so I cannot quote passages, make specific references or confirm the spelling of anything not already in the TextPad spelling dictionary).
On this listening -- actually I'm still listening to the appendix -- I noticed, for the first time, parallels between the relationship of Buckland to the rest of The Shire, and Rohan to Gondor; as emphasized by the different but parallel experiences of Merry and Pipin, mostly in Book 4.
On previous readings and listening, I've always been amused that after Pipin was rumored to be a Prince of Halflings shortly after he arrived in Minis Tirith, a title which he shunned, we discover in "The Scouring of the Shire" that his father is the Thane of The Shire, and in the Author's Notes we learn that Pipin himself will later be the Thane. Therefore, in some respects Pipin is indeed a Prince of Halflings, or at least as close to that title as any Hobbit could (but probably would not) claim.
In the Author's notes we also learn that Merry ends up later as the Master at Brandy Hall, the leader of the Brandybuck clan and of Buckland. From what I know of British and Middle Earthish customs (the later tend to follow the former in many ways) I would have to assume that the office of Master at Brandy Hall was also inherited.
But until I thought about it after this reading, it had never struck me that Pipin, the son of the Thane, pledged himself to Gondor, while Merry the son of the Master at Brandy Hall, pledged himself to Rohan. I then realized that, while there are great differences, there are also some similarities to the relationship between Gondor and Rohan at the end of the Third Age and the beginning of the Fourth Age and between The Shire and Buckland during the same era. Without the maps at hand to confirm this, I think that the geographic relationship may even be similar with Rohan sitting more-or-less North of Gondor, separated by a geographic barrier (the White Mountains) and Buckland sitting North of The Shire, separated by the Brandywine.
The obvious, and distracting, difference between these relationships is that Buckland is considered part of The Shire, whereas Rohan is a separate kingdom from Gondor. But even that is somewhat diminished by the fact, and mentioned in somewhere in the early chapters of Book 1, that many in The Shire, possibly including some Bucklanders, consider Buckland somewhat separate and the people of Buckland as not quite proper (for example, Bucklanders will travel on small boats on the Brandywine while Shire Hobbits eschew any kind of boat).
One other thing that may be a hint or echo of these parallels is that Merry was able to quickly get five ponies for the hobbits to ride when they left the shire, indicating that in a small way Merry was already comfortable with horses, and that Buckland was horse country.
Of course, it is entirely possible that I'm seeing relationships that were never intended or planed out.
