> US Letter: 216 mm x 279 mm
> A4: 210 mm × 297 mm
so it's 18mm longer while being 6mm narrower. At that small a difference, I would assume that a preference of one over the other is similar to that of metric vs. imperial - the one you were raised on just seems right.
Which one did you grow up with?
In other words A4 seems 10% narrower in terms of shape, which isn't insignificant.
Having said that, I'd rather keep A4 given the useful properties described in the article.
I almost always have the feeling that A4 is too big.
If you really want an aesthetically appealing aspect ratio, wouldn't it be 1:(sqrt(5)+1)/2, which is even longer and narrower?
But then I dig deeper, and find this: http://en.wikipedia.org/wiki/Canons_of_page_construction , which seems to indicate that the ideal book page proportions are 2:3, which is again longer and narrower than 1:sqrt(2).
Personally, I find that US Letter is too wide for comfortable reading without using multiple columns of text, and printed manuals using the format are too floppy to be used without a stiff cover page or a binder. And that's just in print. I can't stand it when someone makes a PDF e-book with US Letter sized pages, because it doesn't fit onto any screen that I have without scaling or scrolling. My e-ink screen is 2:3. Most of my computers are 16:9. None of my 5:4 screens rotate to vertical, and that's as close as I can get to 7:9.
How does US Letter even have any fans at all?
Also, in my opinion, B8 seems ideal for playing cards. It is very close to the ID-1 standard, as well. B7 is the same size as ID-3, used for passports.
Is it my imagination or are magazines often taller than A4?