Below is an article I found at the San Mateo County Recorder's website at article points out the importance of deciding whether or not you will change your name before you apply for the marriage license.

What’s In A Name?
Getting Married? Give your last name some extra thought before you tie the knot

(Redwood City, CA) Common law has traditionally and exclusively governed the naming conventions for couples getting married; that will change on January 1, 2009 in California thanks to the State Legislature’s passage of The Name Equality Act of 2007 (AB 102, Chapter 457, Statutes of 2007) which makes two fundamental changes to existing law. The first change affects what can be considered a married legal name and the second change establishes the point in time when a married legal name(s) must be declared and the process for changing married legal names thereafter.

The first change can best be understood by reviewing what’s possible under common law and what will be different under The Name Equality Act of 2007. Today, couples can take their spouse’s name (either spouse, either name), keep their own name, or hyphenate their names together. In addition to these options, on January 1, 2009, couples will also be able to create a new name for themselves by combining into a single last name all or a segment of the current last name or last name of either spouse given at birth.

Take the imaginary example of John Fineman and Carolyn People. This couple could create a new name, taking “Fine” and merging it with “People” so that the couple’s legal married name could be John and Carolyn Finepeople. [Family Code 306.5] “This kind of name might make the couple deliriously happy and very proud while starting a firestorm among the elders in a family,” said Warren Slocum, Chief Elections Officer & Assessor-County Clerk-Recorder.

The second major change is that couples are required to select their married names at the time they apply for and purchase their marriage license. Whatever name(s) are listed on the marriage license are the legal names that each spouse will go by after they marry. Changing a name AFTER the license is issued and BEFORE a couple marries will require the purchase of a new license ($78). Changing a name AFTER the couple is married will require that the couple go to court to effectuate a name change, a costly expense for the couple.

This new law only applies to the changing of the middle or last name. Neither spouse may change their first name using this process. The name indicated on the marriage license application cannot be changed by the County Clerk.

Of special concern to California County Clerks is that a marriage certificate is used by multiple local, state, federal and private agencies all of whom have different rules and/or regulations regarding what documents are acceptable to change a name on their records following a marriage. Couples may want to contact these agencies to verify their requirements prior to applying for their marriage license.

One cautionary note is that some agencies haven’t issued a new ruling relative to this legislation and other agencies may not change their policies, (e.g., recognize a “created new name”) as federal agencies aren’t bound by California law.

“We recommend that all couples getting married in 2009 add one more very important task to the getting married to-do list…think about what you want your married names to be before you apply for your marriage license,” Slocum said.