When I moved into my house (in Brooklyn), I got rid of the old steam radiators and replaced with central air/forced heat.
I did my research, etc etc and decided to go ahead with it and install it with humidifiers.
After years of experience I can tell you that I regret it (though not fully).
Pros:
1. Probably the most cost efficient way of heating.
2. Can get area temperature up quite fast.
3. Much lower installation cost (and simpler maintenance).
Cons:
1. Heat more or less "evenly" distributed, rather than having more heat where needed (next to windows/doors).
2. Ductwork, vents, returns, etc. are a lot more scientific than many people realize. Especially if you are working with rooms rather than open spaces. You really need someone that knows how to properly balance the ductwork (I learned this the very hard way).
3. Unlike radiator based systems, the second the system stops, so could comfort level, as opposed to radiators which remain hot and emit heat even when system is cycled off (due to thermostat reaching set temperature - location of thermostat is also of utmost importance, no matter what kind of heating you install).
4. Radiators are silent (mostly), whereas forced air will always create some level of noise.
Bottom line, in retrospect I think the ideal setup is what a friend of mine did (he could afford anything easily) which was radiant floor heating, with forced air backup. If I were to choose one, I would select radiant floor or radiators.
Interestingly enough, outside of NYC forced air is a lot more prevalent. I think it might have to do with the type of construction as well as the availability/reliability of gas/oil supply.
PM if you want to discuss more about my personal experience.