C++ typedef versus using

I recently saw some code along the lines:

typedef QuiteALongName::SomeVariable SomeVariable;

My first thought was that it might be better to write the code as:

using QuiteALongName::SomeVariable;

But, being a bit rusty, I couldn't quite put my finger on what the differences would be, or whether there were any 'gotchas' to look out for using either approach. Can anyone offer some wisdom?