Freelance Unbound has produced a great post looking at the current state of the journalism jobs market, based on data analysis of Journalism.co.uk’s own job listings.
Judging by their analysis, it seems that roles in specialist business journalism for publications based in London are your best bet:
The most telling items in the chart are the tiny slices for lifestyle and celebrity – the most popular media choices for j-students – and for general news reporting. Very few jobs are advertised in these areas (at least here).