It helps with the networking for some jobs.
Personally I don't know anyone that got a job mentioned here.
But I do know a lot of people who have made contact with people via pprune that have got jobs off the back of that networking.
90% of the jobs aren't even advertised there is no need to as there is huge numbers out there that are kicking about. Generally you can ask a few of the pilots if they know anyone and you will have 5 names within a couple of days all of which personality wise will fit into the team as the pilots don't want to have to work with knobs either.