When Terrain Tools comes out, you can still use your shaders for the terrain. The real beauty of T-Tools is the ability to create a realistic water shader which can detect the shorline and then use an Anything Goos type of shader for creating wave foam or pond scum. You will also be able to use it in the transparency channel to make the water more transparent at the shore and have that fall off as it gets further out to simulate depth. The combination of those two can really aid on water creation. Here are some early tests I did to show what I'm describing.