ildarius - 1:48 pm on Mar 12, 2008 (gmt 0) It all depends on the variables
Without getting too much of your privat information, certain things need to be uncovered in order to judge the situation.
1) How high is your PR (is it worth for them to go after that?)
2) What is your traffic aprox/month (can the conversion rate be high enough for them to make over 5K$)
3) How big is their company? (may be it's more of a brand marketing they are after)
4) How are they paying you?
Find out if may be it's a phishing web-site that's trying to pass for the real thing and wants your links.
It all depends on the variables