Just a word of warning if you provide updated bank details to the Tax Credit office they will only amend the details for the current tax year. If you find yourself claiming for the previous tax year they will make the payment to the bank account details they held previously for that tax year! This could cause problems,if like me you havent claimed anything for years. Due to a change in my circumstances my payment for 09/10 has been sent to the bank account details they were given 7 years ago, which are different from my current bank details.
You will also have problems getting your payment if you separate from your husband and either close the account used in a previous tax year to receive your payments, or transfer it into his sole.
I have just wasted over 2 hours of my life on the phone trying to find out where they sent my money!