My experience is that 3dsmax's tools for baking the normals, kind of suck. When I've baked normals in zbrush, then did the same thing, baking the normals on the same mesh, using Maya's tool instead, the Maya ones looked better. That was an older version of zbrush though, so the tool in there may have been improved since then.
All three apps have a tool to do it - but after using all three, I preferred Maya's tool better (shock and awe - how rare an occurance that is - lol)
Nice. I use a similar method to create a shadow map for my textures. Instead of baking a normal map I bake a lit and shaded color map using a default gray shader. Drop it into Photoshop on top of your color layer, adjust the blending style on the baked map and presto! Instant shading! Makes a great starting base.