But the question is, can bitcoin really substitute dollar or other currency sometime soon?
Yes, once bitcoin payments become reversible.
If the Bitcoin Foundation can get the charge-back coding changes implemented, I think this baby is headed to the moon.
Whattt? You have been around way too long to think that a built in charge-back is the way to go, you should know only a service should allow chargebacks. Imagine if you could randomly charge back cash after trading at a store or on craigslist, terrible idea and you would kill any exchange.