buckworks - 12:35 pm on Apr 10, 2011 (gmt 0)
exact match for our company name
How much does it cost you now to get a visitor to your website? Having the .com under your own control could add up to a lot of type-in traffic over the years from people who are looking for your company. The benefits of that would be hard to predict, but the better known your brand, the more type-ins the .com would get.
On the darker side: what negative effects might arise if someone else got the domain and started using it in a way that created confusion among users or even hurt your reputation? Owning the .com yourself might prevent a lot of problems. The defensive benefits would be hard to measure (how to calculate the value of heading off a problem before it happens?), but it would be something else in favor of buying the domain.
Last thought for now: if you ever wanted to sell the business, owning the .com of the company name would make the acquisition more attractive to potential buyers.