DonnyG is spot on here about sanitizing.

A few side bits:

1) if you decide to take the plunge and take proper care of, and care with, a wooden board, it's worth learning to use a cabinet scraper, which is the best way to get a smooth surface on a piece of wood. It seems easy, but can take a bit of practice to get the hang of, so practice on something else before you decide to clean up all those little cut marks on your board.

2) The other reason to keep your board dry is that wood, being a natural and once living thing, responds very quickly to water and humidity. if you take a thin, cheap board you can see this quite quickly by soaking ONE side of the board and leaving the other dry and then leaving the board to air dry. Alternatively, put a wet board down flat on a counter and leave to dry. As the wet side or the exposed side dries, the fibres shrink and the board will start to 'cup'. You need to keep the exposed side of a permanently mounted board from really getting soaked and left to air dry, and you need to make sure with a small board that you wash in the sink that you treat both sides equally when you wash and leave to dry. Otherwise, you will get cupping and splitting, especially where pieces have been laminated together.

3) I remember an article, probably in the NYT, about some research at UC Davis on wooden boards vs plastic. Their research indicated that bad bacteria were much more likely to develop in the cuts on plastic boards than the cuts on wooden boards, probably because of the tendency for wood to 're-expand' with humidity. Furniture restorers can often fix a simple, small dent in a piece of wood with a steam iron. Same thing happens as you wash the wooden board and the tiny little groves tend to shrink and disappear.

Sanitizer can be aquired at a restaurant supply store (smart & final) or ( Like Pierino suggests) you can use regular bleach. It doesn't take much bleach at all for sanitization, A cap full in my 2 gal bucket when tested with test strips is borderline caustic. @ Gourmando: The kosher salt dries the surface and creates an unlikely microbial enviroment. I apply after wiping down while the surface is still moist and scrape it off when ever I get around to it and it leaves a salty film on the surface (one you can hardly notice) and before I start working on any surface I sanitize, so no the salt doens't ever become a problem for the food. (In case you were wondering) :)

What does layer of kosher salt do? And what kind of sanitized do you use?

After cutting poultry I use a solution of 1 cup water and 2 tablespoons White Vinegar in a spray bottle to sanitize my board. A good spray, 60 seconds, a rinse, and a pat dry and its ready to go.

Most wooden cutting boards are made from a hard wood of some sort that have tighter grain than lets pine or softer woods. I've been using the same stand alone boos bros block for decades and there are few thing you must do. I always keep a 2 gal bucket of sanitizer when working on the block (it sits in the prep sink). I wipe after each use. I sanitized several times after using meat and then I put a layer of kosher salt on it for an extended period of time. I have never had any cracks show up and I never use a hard chopping action that will leave deep dings in it. But like most I prefer wood over poly. It just takes a little discipline

Absolutely clean it after each use. What restaurants use is a combination of bleach and water (low percentage of bleach). I still prefer wooden boards to colored plastic boards. Yeah, they do develop cracks (don't be a sissy). If you sanitize them properly they're safe. My personal favorite is my Chinese ironwood board which I picked up at the Wok Shop in San Francisco. Much better for your knives than synthetic materials.

I use some kosher salt and the ends of a lemon as a scrubber, then a wet wash cloth to wipe off and a quick dry. I usually have separate plastic cutting boards for raw proteins and clean the butcher block each night.