Thanks for all the suggestions. I've received even more via email.
Some of what I've heard so far is...
Strong yes:
- Use the subway and walking to get around
- See the art museums (Met and/or MOMA)
- Skip the bus tours
- See other parts of the city beyond Manhattan
- Eat like a pig, then walk it off
- A sharp wit should be an adequate defensive weapon
- Brooklyn Bridge
- Ground zero
Mixed:
- Times Square
- Chinatown
- Central Park
Strong no:
- Empire State Building
- Statue of Liberty
Erin and I are looking into doing a trip longer than 3 days. If we can't secure extra childcare, then we may fly out together, and I'll hang out longer in the city (maybe for 7 days), while she returns early. Erin doesn't handle long walks well, since she currently has a foot condition known as a stone bruise. So I can do all the walking stuff after she leaves. I love long walks.