What factors can increase my chance of getting an upgrade to first class?

What factors can increase my chance of getting an upgrade to first class?

Jen Leo (Daily Deal Blogger, LA Times Travel Section) gives expert video advice on: What is "economy plus" and how can it help me get a better seat?; What are "exit row" seats and why are they better?; What factors can increase my chance of getting an upgrade to first class? and more...