I think a .com name is important, but I can't back that up with any real evidence.
I know of a little anecdotal evidence: A .org I know of used to routinely have to remind people it was .org, not .com. The owner of another .org I know of once stated bluntly they "farked up" by not buying the .com version as well, which was bought at some point by a company (using the same name, if I recall correctly -- physically located elsewhere). And, of course, there is the infamous whitehouse .com to take advantage of the fact that even for .gov sites, people mentally default to the .com mode.
No formal studies or anything (that I know of), but there is some anecdotal evidence that it makes a difference of some sort.
I know of a little anecdotal evidence: A .org I know of used to routinely have to remind people it was .org, not .com. The owner of another .org I know of once stated bluntly they "farked up" by not buying the .com version as well, which was bought at some point by a company (using the same name, if I recall correctly -- physically located elsewhere). And, of course, there is the infamous whitehouse .com to take advantage of the fact that even for .gov sites, people mentally default to the .com mode.
No formal studies or anything (that I know of), but there is some anecdotal evidence that it makes a difference of some sort.