We have a nice set of Quisinart nylon/plastic cutting boards that now have a bunch of knife scoring marks in them, which I'm sure must trap bacteria and germs. I would think that wood would also absorb stuff.
I have seen the cutting board protective "sheets" that are disposable. Has anyone used these? I may give them a try, but as many times as I wash and reuse my cutting boards, they may be too expensive.