Average confirmation time of ~10 minutes is still quite significant. Won't cause any problem for the online shoppers. But people who want to use BTC for retail shopping won't be able to do it.
Retail transactions are routinely performed at 0 confirmations, because transaction propagation alone validates any given transaction better than any other payment method in existence already. 10 minute blocks being a hindrance to retail application is the biggest myth that absolutely refuses to die.
Except as a business owner I'm not giving you ANYTHING till I see 3 confirmations.
There is really no need for that. Once you see the transaction go through, even without confirmations, you are safe.
The transaction will end up going through...there is no way for the purchaser to reverse it once you see it show up.
OK, I thought that having 51% of the hashing power allows you to do just that and more....
Exactly! Since nobody controls or will control 51% of the hashing power, there is no fear for a business owner.
You could double spend the transaction.
If you control 10% of the hash power, you can replace the Tx in your mempool with one that overrides the existing one. It'll have a 10% chance of working.
Who controls even 10% of the hashpower??
And why would you risk losing your 25 bitcoin block reward just to have a small chance of double-spending some satoshi at your local starbucks, lol.
Any amount of money that would be comparable to the current block reward (25 btc) would wait for one confirmation at least.
Double spending <<1 BTC isn't worth the pain it would take to have the small chance of succeeding.
Do you remember when grocery stores used to cash checks for you so you could do your shopping? People defrauded them all the time and they'd put up your picture and never accept checks from you again. It was part of the cost of doing business but brought in a lot of customers because it was convenient.