Family budget for 2008

All these years, we never had a budget. Money comes, money goes.

However, this year we bought a bigger house, and suddenly money is getting tight. So I worked up a buget plan for 2008:
Our buget, Model buget from CNN
Tax: (fed, state, SSN, medicare, property): 30% 25% California is least tax friendly state
Housing & Debt: (mortgage, credit card, etc): 25% 30% We have no other debt
Insurance (heath, life, car, home, disability, etc): 1.5% 4% Are we under insured?
Living expenses(everything except mortgage): 26% 26% Right on target, just barely
Saving (401k, 529, investment): 17.5% 15% What is savings, anyway?

How do other people save 30~40% of their gross income?