Here's a "raw report" press release from the Franchise Tax Board. (They'd like you to pay your taxes on time, and correctly!)

Last Minute Filing Tip: Tax Errors Can Cause Major Delays to Your Refund
 
With two weeks left before the April 15 tax deadline, the Franchise Tax Board (FTB) today offered last minute tips for taxpayers and outlines the top 10 tax filing errors that delay refunds.
 
“There is time left for even the most complicated returns, and we offer a number of tools that can help you speed up your refund and prevent errors in the filing process,” said State Controller and FTB Chair John Chiang. “A taxpayer can file his or her return online today and have a refund in the bank well before April 15.”
 
Speed Up Your Refund
Taxpayers who file online and have their refunds issued by direct deposit often get refunds within a week. Paper returns requesting check-issued refunds will take six to eight weeks.
 
Avoid Common Errors
The 10 most common errors include:
1) Estimated Tax Payments – Claimed amounts do not match FTB records.
2) Payments and Credits – Amounts either incorrectly added or subtracted from total tax.
3) Withholding Credits - Amount of withholding claimed does not match W-2s.
4) Estimated Tax Transfer – Incorrect refund amount transferred from previous tax year.
5) Excess State or Voluntary Plan Disability Insurance (SDI/VPDI) -- Excess amount is not substantiated.
6) Exemption Credits – Claimed amounts miscalculated due to income limitations or computation errors.
7) Amended Returns - Incorrect amounts transferred from original return to amended return.
8) Tax – Wrong amounts selected from the tax table on paper returns.
9) Renter’s Credit – Wrong amounts claimed for filing status, income limits exceeded, or not qualified due to residency status.
10) Deductions – Incorrect amounts claimed for standard or itemized deductions.
 
FTB’s new “My FTB Account” service can help taxpayers avoid many of these errors by allowing them to view their estimated tax payments, California wage and withholding information, and other useful information online. Electronic filing programs, like CalFile and ReadyReturn, also catch many errors before the return is submitted.
 
Need Extra Time?
California automatically gives taxpayers a filing extension on their state returns to October 15. But if you owe tax this year, make sure you pay that amount by April 15 to avoid interest and penalties. If you can’t afford to pay by April 15, you can request a payment plan online. You will generally qualify if you owe less than $25,000 and can pay your taxes within five years.