Some operator overloading, and inline support for XML documentation, and that's about it. C# and VB.NET both compile to exactly the same MSIL bytecode underneath (more or less) anyway. One huge advantage is does have though is that it doesn't include all the VB backwards compatability stuff, so you don't have to worry about doing things the "right" way.
However, if he knowns what he is doing, there's no reason he should choose one over the other. If he is just learning, however, he should probably go with C#, since it has less room to be sloppy.