If you are convinced that .com is parked domain mega-corp that you won't have to compete with, .co is OK if you can also get .net/.org, so can 'own' the brand.

If you are convinced that .com is parked domain mega-corp that you won't have to compete with, .co is OK if you can also get .net/.org, so can 'own' the brand. Assuming you are startup where company name is product name, I think the more important thing is to be able to get the matching twitter and facebook ID, if you can get same same as what you are targeting .co for.