New credit card if buying home next year?

[Anonymous]

Hello,

I am considering opening a new credit card that provides cash rewards (American Express Blue Cash).  I am also planning to take out a mortgage next August or September of 2010.  Would the new credit card prevent me from getting the best possible rate on the mortgage?  I currently have one credit card (MasterCard) in my name and an excellent FICO score with no debt other that what I pay off in full each month.  

Thank you in advance for your time and advice.

[Anonymous]

Actually, having an additional card would probably help you. By the time you're ready to apply for the mortgage, you'll have a year's worth of history and the newness of the card won't hurt you as much as it would if you were looking to buy soon.