Notice how you are fudging the issue (as almost everyone seems to): peer to peer exchange of crypto/crypto vs peer to peer exchange of crypto/fiat.
The latter is the real problem (although I'm not saying the first one is particularly easy).
Why bother with fiat? It is a doomed experiment. The banksters had their day now it is time for them and their puppet politicians to get out of the way because of a new revolution.
People who keep comparing crypto to fiat in terms of worth just don't get it.
If you don't use fiat, what are you exchanging? Bitcoins for...?
What? Are you serious?
For goods and services, and if you must have a physical store of wealth gold and silver.
Fiat is nothing more than modern day slavery. It is time for it to go the way of the dinosaur. They print it out of thin air with no finite level. With every dollar created $1.05 is owed to the banksters, thus ensuring debt slavery.
http://www.youtube.com/watch?v=lu_VqX6J93k
Stop being obtuse, it's pretty obvious you still need fiat at this point in Bitcoin's life cycle. Bitcoin is generated through the mining process, which also keeps the network integrity in tact, all of which costs electricity. Last I checked, the major electric companies are not accepting Bitcoin as payment so you're still going to have to use fiat. A pure goods/services to Bitcoin economy would be very small in scale. Insignificant.
Same with gold, how are you going to get that gold? Pan for it? Mow someone's lawn for gold? You can use Bitcoin as a MEDIUM OF EXCHANGE, but what does that have to do with eliminating the exchanges? Nothing.