Neptune is the second of the generational planets, spending fourteen years in each sign. Everyone born within that period will have Neptune in the same sign. By itself, Neptune's sign is not the most important factor in your chart; however, this placement symbolizes what was going on in the world at the time you were born, which has left an imprint on you.
You and members of your generation are each imbued with this particular energy, and in some ways it characterizes everyone born during this time. Each individual will express it in their own way, some more strongly than others. Neptune in Leo indicates the reemergence of the spiritual individual. In some way, you and members of your generation are willing to sacrifice yourselves for an ideal. There is great compassion and an opening of the heart. You are a group of sensitive and idealistic souls.