There’s a new Kindle in my house, and we’re excited about it. But I wonder if the mainstreaming of the e-book is taking something away from our relationships.

Going back. My wife and I are book people. Readers. My wife has spent over 20 years in book publishing and is currently the senior publicity executive at a large publishing house. I used to be a writer, and while my writing was for the screen any writer is by definition a serial gobbler of books. We’re both pro-Kindle, at least to the point of giving that thin little machine a chance to show us that we can happily read on it.

The theoretical pros are compelling.  One way of looking at the publishing industry is that they are value adders to paper sales. Using less paper seems like a good, green thing, leaving them as sellers of pure value. Just the savings on mailing galleys around is a huge cost reduction to the business. With readership on the decline, that dollar savings is probably saving jobs.

Carrying a kindle is easier than carrying paper books, particularly if you, like I, usually have more than one going at a time and also read newspapers and magazines. And it’s connected, so you can also read blogs on it.

But there’s a cost. And it may seem ephemeral — probably more so the younger you are.

Used to be that when you would visit someone for the first time, you would scan their CD collection — ok, I started to write “record collection” because that’s where it started for me — and their bookshelf. You would get an idea of the personality of your host their experiences and interests. These personal identifiers were conversation starters or at least access points to each other. Today, you almost never see a CD rack. Everything is ripped to the computer. And that’s a good thing. People have their collections shared, they have them streamed through Express networks throughout the house, they can shuffle endlessly and create a soundtrack of everything they like. But it is one less way I get to know you when I walk through your door.

Now take away the bookshelf too.

The bookshelf isn’t only an outbound visualization of your taste or intellect. It’s a cliche to point out that physical books carry emotional reference. But there have been so many times when I wanted to read something but didn’t know what and scanned my bookshelf until something popped out at me. Something either I hadn’t read yet or that seemed to push itself out on the shelf towards me just from a glimpse of the art on the spine. A black and white scroll down a kindle list isn’t going to do that for me. I know because I have the same frustration with running down the list of music I have on my iPod.

At the same time as this is happening, there has been a huge shift towards furnishing your home from mega-companies like Pottery Barn. We don’t really buy locally anymore, we buy at the mall or from catalogs. So, take away the indicators of personal taste, reduce my options, and furnish with stuff that everyone else also has access to and you’re left with very limited ways to show your personality in your home. The conversation starter is, “Hey, I’ve got that same chair.” Oh. Cool.

This change in how we get our content certainly changes how marketing messages are delivered and creates new business models.  But the loss is something that means nothing to a marketer and everything to a potential friend. Everything, but you don’t necessarily miss an absent clue to a conversation that hasn’t started.

But, as with almost everything, it’s more complicated than that.  Because while these tangible channels of personal expression are going away, there is a shift going on to express ever more widely as  people use social networks to express their “identifiers” in a big way. Think of all the little Facebook games and apps: cities I’ve been (I’m a traveler, I can talk coherently about Budapest), Visual Bookshelf (I’m a reader and if you want to talk about Harlan Ellison I’m up for it). Or on Flickr (you can gently mock me about the piture where I have a keg on my head) or YouTube (can you believe my son did that?). In fact Delicious Library lets you scan the UPC symbols of your books, CD’s, and DVD’s to create virtual, visual bookshelves showing them off.

Now, posting in public is different from having these displays more privately for invited guests to your home.  Maybe the difference, though, is more in the delivery. It’s that they’re portable and publishable.  And also programmatic.  What does seem harder to replace is that tactile intimacy, that jolt of recognition when you walk into a new acquaintance’s place, look around, and think: “Yeah, we could be friends.”