Dear Rich Staff is sorry to hear that you are no longer the master of your domain ... and yes, anybody can be a dot-org.
The skinny on TLDS. When top level domain names (TLDs) such as .com, .org, .gov, .net, and .edu were created by the Internet Corporation for Assigned Names and Numbers (ICANN), the intention was that each TLD would cater to a specific type of domain name holder. For example, .org was intended for nonprofits, and .net for network related entities. But only some TLDs are really restricted--for example, .edu for educational institutions, .gov for government agencies, and .mil for military agencies. To get one of these you must qualify. But that’s not the case with .org, .net, and .com. all of which can be obtained freely by just about anyone, for any purpose.
What can you do about the interloper? If someone has taken your company’s trademark and is using it in bad faith to compete against your business as a .org, you can either sue for cybersquatting in U.S. federal court (very expensive), or you can request ICANN arbitration (approximately $1500 if you use only one arbitrator). We discussed cybersquatting in a recent post.
P.S. Coming Soon: Custom TLDs. ICANN has announced that companies can – commencing January 12, 2012 -- buy custom TLDS. For example, Nike can buy exclusive rights to .NIKE and Apple can buy .APPLE. Supposedly these custom domains will sell for $185,000, so it's for serious players only.