Excession demonstrated that ship-to-ship-chatting gets tedious very quickly (as the ships have no distinct personalities - even when Banks tries to create this, we know it is meaningless, as the Minds cannot have character flaws).
Whoah, whoah, whoah...settle down. The Minds have all variety of character flaws and eccentricities. Without digging out the books and combing through them I have no chance of getting the ship names right, but think of the single mindedness of the warship ("
Will you accept my mind-state!") in
Excession, or the aloof ponderousness of the Sleeper Service (think I got that one right), or in that first meeting of the ITG while discussing the excession all the various personalities at work (one responding in as purple a prose as it could muster, and another, not to be out done, answering in iambic pentameter - that had me laughing out loud for a good few minutes), or the feigned disinterest but actual intensity of the SC ship in
Surface Detail, or the pompous GSV in
The Hydrogen Sonata, or, in that non-spatial meeting mansion the eccentric ship that manifests as only a cloud that, as the conversation progresses and gets a bit heated, starts raining.
Banks gives his ship Minds as much if not more character than his people. They are capable of unknowable brainpower (compared to the feeble human mind), but they are all different and become their own distinct personalities, and more so the older they are.
Or, on even a larger scale than ship Minds, think of the excession itself, at the very end of the book, wanting from now on to be known as The Excession (cue sunglasses smileyface), that's a huge amount of character added, last minute, to an otherwise unknowable infinitely superior being.
I think it became more clear that it was some type of neck-tie.
Funny.