If you're in the top 25, you can make great money because they double your earnings. I'm a generalist and it's really only worth it during the peak times. Any other time and you'll just sit there for a long time.
Plus you have the chance to win one of those bonus tickets that they've been doing.
Also, they deduct 2 dollars every time you put more money on your balance. When that's like 20 questions, it gets kinda frustrating and not the fast 'Oh I need a pizza let me get on the computer for 5 minutes' source that I hoped it would be.