Have 2009. New PC Comes With 2010 Trial. What Do I Do?

Okay, so the computer we're currently using has Norton 2009 and is completely updated with 107 days remaining on the current subscription. We just got a new computer that comes with a 30 day trail for Norton 2010. The PC hasn't even been plugged in yet because we're not sure what to do. 

 

I'm worried about what would happen to our current subscription with the version we have now if we activate 2010 and the 30 trial. Will we lose our current subscription? How does this work?

 

Any help would be greatly appreciated!