Agree with what davidjohnson has said above - it is currently in BAA's interest not to attract new airlines because it will then make their appeals look unfounded.
However, it is a very sad state of affairs to watch the place diminish the way it has. I flew from Stansted a couple of weekends ago, approx 9am on a Sunday which is traditionally a very quiet time of day at the airport, even more so now with all of the cutbacks. I turned up with 90 minutes to spare knowing that it should be pretty quiet. Well, the terminal was very quiet overall, however they only had a handful of x-rays open and so we still queued for 25 minutes in the end and I then waited another 10 minutes for my bag to be hand searched by a miserable member of staff as there were 4 or 5 people in front of me waiting for the same! For an airport that can supposedly cater for double the amount of passengers that it is currently handling, it really isn't good enough for it to be such a mind numbing and slow experience.
I also witnessed a staff member threatening to 'phone the police' if one gentleman did not listen to the advice that his bag was over Ryanair's limit and that he'd have to go back to the check-in desk and pay for it to go as hold luggage. Basically he was just pleading that he was given the chance to 'give it a go' and that it was Ryanair's problem at the gate if it didn't meet the limits. Maybe someone in the know can tell me whether it is a security staff responsibility to enforce such rules, as I really don't know the answer to that one? Either way I think that the situation could have been much better handled than threatening to phone the police.
This year I've only braved Stansted once, despite only living a few miles away. It's a 50 mile journey to Gatwick for me, yet time and time again this year (5 or 6 trips so far) it throws up better choices, more airlines/destinations, and a nicer experience. It would appear that for the time being this will only get worse as Easyjet move aircraft to Southend and gradually move other routes to Gatwick.