Credit card transactions between friends still aren't that easy. Not everyone likes (or has) Paypal, etc.
Something like this would be extremely helpful for situations like multiple couples renting a beach house or people chipping in for an expensive gift for somebody else.
I have used WePay (https://www.wepay.com/) in the past and really liked it. They charge less than Mint is planning on charging. For credit cards its 3.5% with a 50 cent min. The fee is less if you use your bank account.
Credit cards are the wrong payment method for paying friends. Credit cards make sense for strangers paying strangers where the payment needs to occur instantly and at least one party is willing to pay up to 3%, none of these being the case when paying friends.
To be annoying by tacking a long, overly thought-out comment onto yours (sorry): Agree with this root sentiment, for many other things that used to be done casually and amicably in real life and are now replaced by process-driven, efficiency-focused and sterilized online versions. However I think that such a substitute is ok, or better- great, when (a) the thing just wouldn't happen at all in the first place because it's just too difficult (e.g. say keeping in regular touch with a very large group of far away friends) or (b) it's not pleasant in its real-life instantiation anyways. I think nagging friends to pay you back esp. for small amounts satisfies both of these criteria.
Something like this would be extremely helpful for situations like multiple couples renting a beach house or people chipping in for an expensive gift for somebody else.