the average joe doesn't really stand a chance getting a good domain because the people into them for a living own massive numbers of them as evidenced by the above post.  Personally I wouldn't spend a dime on any of those domains because a good business will do well through word of mouth, just like a site like coinbase.com has done which really you wouldn't figure would be a bitcoin exchange looking at it. I suppose having bitcoin in the name might help them and if they were smart they'd take their profits and buy up a better name.  I'd say maybe after you have some cash flow use it to buy a better domain if it's needed.. but a crappy service on a good domain is still a crappy service.

In any case I look forward to the day a domain name can be any extension and shortages of good names become somewhat a thing of the past. That day is getting closer and closer. Of course if there are a million possible extensions of a site you'll find a person buying a million of them up...