Hi, Tom.
Absolutely! Leaves are a wonderful addition to your soil. If you introduce them in the fall, they have the winter/early spring to break down for spring planting. The worms really do love them, and we really do love the worms.
One thing to watch out for though-Walnut leaves. Walnut trees produce a chemical that acts like a poison to inhibit growth of <potential> competitors. I have chatted with another experienced gardener who unwittingly included walnut leaves a few falls ago. He's extra careful now to avoid a repeat incident.
Some people swear by the 'only leaves' ammendment; others swear by "only straw" (with cottonseed meal), and others swear by the "only manure". I fall into yet another camp-I'll add everything I can get my hands on. I add:
leaves
llama manure
steer manure
alfalfa
kelp meal
fish meal/extract
liquid seaweed
compost tea (made from worm castings)
green manure (Austrian field peas)
coffee grounds (hundreds of pounds)
grass clippings
kitchen scraps
fish waste rescued from the fish market's garbage cans (bass omatic)
used hops from a local micro-brewery
tea leaves from a local chai tea maker
lots of compost
There are probably more 'ingredients' but my mind wanders......
