It depends if you are targeting specific traffic or not. In general you can't go wrong with a .com but if you are in a country that prefers .cctld you might want to get that - or heck get both if you can
Best to get both if you can swing the price.
It secures your investment if you intend on
developing. It also betters your chances if
you intend on flipping [assuming the name
is fairly common]. IMO.