Does putting knives in a wooden block blade down wear out the blade?

I'm not a whittler, but I think that what causes the blade to wear is pulling it across the wood. The blade should be fine as long as it is drawn lengthwise (like you are cutting something in half). Blades are very strong this way, but since the edge is very thin, it can easily be bent by having things pull across it.

Since wood is much softer than metal, I suspect there would be very little impact on the integrity of the blade. It it were pushed very hard into the wood, it might bend, but under normal use, I can't see any problems.

It shouldn't matter all that much. I prefer a magnetic strip on the wall, though.

It's much better to put the knife in a wooden block than to put it in a drawer and have it rattle around with other metallic objects. Most pro knife sets come with a wooden block so I would assume that is the preferred storage method.

If you are concerned that pulling the knives out along the wood will dull the blade than as you pull out, also pull away from the blade side so the knife blade doesn't rub against the wood.

We have two knife blocks. One has vertical holes, the other has horizontal holes. The horizontal block gives us all the advantages of wood, without the big disadvantage you just pointed out. The cutting edges don't rest against wood all the time, and are less likely to be in contact with said wood when being placed/removed.

Technically, yes. While wood is a preferable surface to many others for drawing your blade across it will still cause wear. If you're using a block, the slots should be horizontal.

Your knife block is poorly designed. I have a Shun knife block, the blades go in sideways. I just searched for J.A. Henckels and Wusthof blocks on Amazon as well, all horizontal.

Is this worth buying a new block over? Probably not, as the other answers in this thread indicate, it's not that big of a deal. It is less than ideal however.

Frankly, I think the constant up and down and sliding across the maple cutting board will do much more to dull my knives than storing them in a vertical slot block.

Yes, they can wear a bit in a vertical block, but only if you store them point-side down. When I had a vertical block, I stored them points-up. Assuming there's a little extra room in the slots, the tip should touch nothing when you remove the knives.

As Chris Cudmore stated, actual use of the knife on a wood cutting board will dull the blade far more. My guess would be that one average knife use dulls as much as 100's of in and outs of the block. And if you carefully pull the knife out and replace it so the edge does not even slide on the wood (as I do), then no block damage at all.