People aren't going to like what I'm going to say but it needs to be said regardless.
The only way bitcoin or any other alternative currencies will become mainstream is if enough infrastructure is built around it.
Person A sending bitcoins to person B (irreversibly) is simply not going to cut it. There is no inherent trust between both parties. We need 3rd party business (banks, insurers,lenders, exchanges etc) to build trust.
I doubt it. I bought a $1,600 domain using namecheap and sent them irreversible funds by Bitcoin. OH NOES was I worried, did I use a trusted bank as a third party? Nope. namecheap has a solid reputable business and they stand to lose a lot ripping me off. I had not a second of doubt/fear sending them the BTC.
Imagine your local power company, amazon.com, newegg, namecheap, (insert company you already trust here) asked you to pay with Bitcoins would you have a problem? I don't think most people would.
Now for fly by the night never heard of the "company" (which isn't even a real company) until they got out of noob jail and starting asking for tens of thousands of bitcoins in "pre-orders" well yeah you probably want to escrow that, then again if they asked for cash you probably would want to escrow it just the same.
I pay for gas the old-fashioned way, with cash. I walk into the store, "$60 on pump #3", give her $60 and leave without a receipt. Every time I think how easy would it be for the teller to just pocket the money and say she has no idea what I'm talking about when I come back and ask why pump #3 isn't on. Haven't been scammed yet.