"Believe it or not, Camera Raw is great for creating black-and-white conversions. Start by opening a RAW image, then lowering the Saturation to –100. Adjust the Exposure and Shadows sliders to create a nice contrasty image, then drag the Contrast slider to the right to give the image even more contrast. Now try all the different White Balance presets until you find the one that looks best for your particular conversion. You can even add sharpening if you like by clicking on the Detail tab and adjusting the Sharpness slider. And best of all, you can create a surprisingly good black-and-white image before it actually enters Photoshop CS2."
Source: Planet Photoshop