This is really interesting. Like you avalon, I was taught that brain cells were finite. This new info seems to be just the tip of a massive iceberg. Its amazes me how much we know about our world but don’t know about ourselves.
Wait, I thought the hippocampus processed memories, not stored them. 
Guadere:
Properly spoken: The Hippocampus is involved in the formation of new memories…people with damage to the Hippocampus can not form new memories (as in early Alzheimers). Exactly where the memories go from there is not exactly certain, and may depend upon the type of information stored in the memory. I have heard the frontal cortex tagged for this sort of thing, though auditory memories might go to the temporal lobe, etc. How they get from point A to point B I am not sure (I am not sure if that is known). I wish I had my physio book on hand, I could be more specific. This is (obviously) not my area of expertise.
Hmmm…pondering…it could be the newly formed neurons in the hypocampus throw up axons toward the higher cortex and any memory storage areas and transmit the memories thusly. I am speculating of course.