However, I will say this. Anyone that relies on AdSense alone to cover their costs will likely fail at some point. Diversify the income streams.
Yes! Relying on AdSense to "pay the bills" is just plain stupid. There is absolutely no control over earnings. I'd be like having a job where the boss pays you "what he feels like" once a month. Use AdSense for "extra" income, and your job so the bills get paid.