Wood is no good.
Tile is in style.
Ceramic tile or stone is by far the best floor covering solution for bathrooms.
Has been for a long time.
And you don't have to use concrete board, otherwise known as cementitious backerboard units.
There is water-resistent underlayments, such as Schluter's Ditra and Georgia Pacific's DensShield, that are much up to date materials that are esier to install and will last longer.