M.B.
The daffodils will continue to come up and bloom each year, if you don't dig them up...
Also, don't cut the foliage back until the foliage is dry and brown... as long as it is green, it is storing food in the bulbs for next years flowers.
When you do trim the foliage, just trim it back to about an inch or so of the ground.
http://forums2.gardenweb.com/forums/load/bulbs/msg0410264...
http://www.ehow.com/facts_###-###-####_prune-daffodils.html
http://www.blomsbulbs.com/growing/autumn/daffodils_faq