I am currently gutting my entire bathroom. I plan on replacing wallboard with the 'green'wallboard designed for wet applications. My question: should I use a cement board product around the tub for the tile, or it the green board OK? Secondly, is there any special preparation I need to do so that the grout remains water tight?

The green boared will hold up for a period of time but will eventially fail. THe cement board is just as easy to work with and will last forever. The tile will also adhere better to the cement board. Any other questions you can email me MKUHL@SOCKET.NET
Matt

The greenboard is fine for all areas except around the tub. Then you want cement board.
Greenboard is water resistant, not waterproof.