Since it is a 1099 form, that means nothing was withheld for SS. Therefore, while you will likely not owe any income taxes on it, you WILL owe self-employment tax. Self-employment taxes cover the employer and employee portions of SS/Medicare taxes. They get automatically deducted for employees and show on that W2 your wife got. Pretty much everyone has to pay SS/Medicare/Withholding taxes even when they don't owe income taxes. Employees get theirs automatically deducted BEFORE they get their paychecks, so they don't have to worry about owing it. But people who are contractors/sub-contractors do not get it withheld and owe it by the end of the year.
HTH
Rusty (who is a sub-contractor)
edited to add: The nice part is that you get to deduct your business expenses from that total amount and then only owe self-employment tax on the remainder.