Not easy to answer, given the limited amount of info you have given..
One thing to consider is, was the new trademark owner already trading and was his brand popular when you registered the domain ?
Owning an undeveloped domain does not give you any TM rights.
The reg date is not as important as the first use in commerce date. While they do not necessarily have a claim on your domain, you definitely can not use the domain in the same area they are doing business in...
I agree very much with Dub, if someone had registered amazon.whatever before their rise to power and dominance and someone halfway around the world wanted to buy it because it wasn't as yet trademarked they would have no leg to stand on.
But the courts don't usually consider who got there first, just who has more money to pay/bribe them with.
If a company has a trademark and they can convince a court that they want it and can put their kids through college for the help they wil simply take it.
You need to get specialised legal advice for something like this..
It depends. I wish I knew the name I could help you better, but there was a time when I owned a name that was all mine for years. I received an email out of the blue from someone who offered me $500.00 to buy it, or get sued for TM infringement. I get these all of the time so I looked up the trademark and sure enough, they just trademarked the exact name.
I sent an email reply stating that we are currently in the process of developing the name and have owned it since 1993. If you want to reimburse us the $89,909.00 so far in development fees, plus another $100K for us to abandon the enterprise we will consider it.
To put a long story short, after 3 weeks I cashed a check for $85K and called it a day.
I agree with Dub, but with business anything is possible. They may not want to spend the attorney fees in court battling it out. What I have done with my really good names is TM them. Its cheap at the state level and is a double whammy of support if needed.
If you develop the domain into a different area of goods and services than that of the trademark owner you have a chance. The fact that you had it first but didn't develop it until after the trademark owner will be held against you.....