Heya,
Just starting out and pondering whether to go Mobile, but got a little discouraged when someone on STM said it's nearly impossible to make a profit from Decisive nowadays because of low quality traffic. Does that apply for other mobile platforms as well? I want to find my niche, like mobile gaming, and stick to it, but I'm not sure mobile is right for me. Is the success rate higher or lower for mobile?
theres a lot more traffic out there than just decisive
Try Go2Mobi, you can have an AM there, she will help if you have problems, also quite newbie friendly and gives more data than decisive.
There are other mobile traffic sources (like Go2Mobi) if you dont want Decisive.
Thinking that if 1 traffic source isnt good enough than the whole vertical isnt worthwhile is wrong.
1 affiliates bad traffic source can be the other`s goldmine.
Is mobile right for you? You can probably answer it better than anyone else. But how can you know without even trying?
I can assure you affiliates are making money with mobile. A lot of money.
Also doing a lot of money with desktop 
Mobile is hot right now, how about trying Go2mobi, Millennialmedia or Admob?