It's a personal preference. What do YOU want?

I recommend tile since you cannot achieve a water tight seal with wood baseboards.

I like the look and warmth of the wood, but it's a personal preference.

As the others have mentioned, it is totally personal preference. I prefer wood b/c to me tile "baseboards" look commercial if the tile does not continue up the wall to at least the level of a chair rail.

You can use pvc, also. It looks just like wood but doesn't warp or split. They are using it a lot on the exterior of houses because it holds up better, and one of my bathroom contractors recommended it over wood.

Depends on the look you're trying to achieve. Here, using a solitary wood baseboard would be out of place.

Chinese quartzite tiling, Maax Palace bubbleair, Kohler fixtures and fittings.

Worthy, whose bathroom is that? Is it yours?

Worthy is right, wood would be out of place in that bath.

disney, I have PVC beadboard in my guest bath and we decided to use the wood moldings. They look great together. You can't tell the PVC is PVC unless you touch it.