Interesting question LogoItForward. I work for a law firm that specialzes in intellectual property and I shared your inquiry with Brian Hall, an attorney, here at Traverse Legal. He provided this response:
It is always worth the small investment to register the domain name corresponding to your business. If you do not, someone else will and it will cost you more money to get it back. However, you should be aware that even though the domain name may be available, you want to make sure registering and using it does not subject you to claims of cybersquatting. Cybersquatting is the registration or use of a domain name with a bad faith intent to profit. Given your legitimate business, it is unlikely that it would qualify as cybersquatting. However, you would be well-served to have a trademark availability assessment performed, and if clear, seek trademark registration protection for your mark. A trademark registration attorney can help you. Note this is not legal advice and does not create an attorney-client relationship; you should retain legal counsel should you wish to purse the above-identified issues.
Additionally, our website at http://traverselegal.com/ provides substantial information on domain matters and trademarks.
Hope this is helpful.
Pat