I have brokered .com domains for many startups over the past few years, and I can say almost every time the domain was fairly priced and a deal was reached without too much negotiating or time wasted.

I really think a lot of startups shoot themselves in the foot by just saying "everything in .com is taken." Well maybe, but that doesn't mean you can't pay $2-5k and actually secure your domain.

What I am saying is shelling out a few grand now for the appropriate .com will save you loads of time and headaches than if you try to brand on non dot-com and eventually realize you can't live without it.