Further on that point, you may or may not have to actually ask the credit bureau to remove that item on your credit report.  Just check the report to make sure that it is off if it have a huge effect on your report and if you are planning to do any type of application.

If the card is old, there is really no reason to remove it, only remove the younger one if it impedes your ability to obtain new credit.  This means that if banks' calculator is telling them that you only can have up to 100k in total and you already have 105k, then you will need to get rid of a card to apply for the new card that you want.  The Best Buy card is the best example in my case as it takes up 5k worth of credit and I'm finding out that the credit lines for my newer cards are getting smaller and smaller even with a expanding income.  My family members are getting way bigger credit lines even though they have smaller income.

The other reason to cancel young cards is to churn the cards for signup points/miles.  So cancel, wait 2 years, rinse and repeat.