I think square would make the book look more unique, add some style

i would do square, that way on some pages you could use portrait pictures but on others, you can stretch the picture across two pages for a landscape. that's just what i think.

I think Portrait is better because it looks more professional.
Plus you can fit more on a portait paper.

though I choose the portrait, I think that only depends on the feeling that you wanna create unto the image.

portrait is very personal, a bit like a two way conversation between the viewer and the photo, but landscape looks a bit more impersonal but more like its the photo speaking for itself, it's like a monologue but an interesting one. and square is very restrictive but it has a naughty feeling of being the peeping tom ( heh, I always thought that about the square format)

but it all depends of the image, so choose the formats that will fit the character.

Portrait!

I would say portrait.

portriat

definitely the portrait

So, i voted for Portrait. The format is way better and i personally think it shows the Photo's Beautifully and nicely. Yes you should go by your own opinions, but its all good. Thank's for axing us.

my brain broke.

Each has it's advantages, but landscape and square might give you more negative space to play with for the text you include in the comment section. Mentally I find it more difficult to work with the rule of thirds in a portrait setting, but it's nice to be surprised.

I voted... but I'm still torn between square and landscape.

(and yes, this lurker finally sees the sunlight. CAPSLOCK!!!!)