Note that many websites that started out on uncommon TLDs (the .com, .me, .net are Top Level Domains, or TLDs) eventually moved to .com. Take, for example, del.icio.us - it's now delicious.com. Of course, they had to gain the capital to buy the better domain, so you might not have that option.
However, many oddly named .coms are very successful. flickr, for example, does not seem to suffer due to their name.
But it depends on your audience and how you advertise. If your website is largely going to be visited by computer savvy people, or is always going to be linked via internet advertising, then, other than branding, you don't need to worry too much about it. If people want to get to you they'll google your company's name.
However, if your audience consists of "the average person" and is advertised in print, you need to make it easy to type in and understand, and unfortunately people assume .com for their primary internet usage.