Bitcoin cannot replace the credit card today, simply because of it's 10 minute transaction time. Impractical in real world situations especially since it takes a few seconds(1-3) for you to be able to transfer money on a credit card, unlike Bitcoins 10-40minute wait...
Really? Because I can transfer BTC just as quickly as I can make a purchase with a credit card. The fact that my Bitcoins appear in my wallet BEFORE the Blockchain verifies the transaction is actually one of Bitcoins strengths. Ever seen "pending deposits" on your bank account? You know, the ones that can take days to clear before you actually get your money? Fuck that. I WANT MY BTC!!!
Hehe! Actually I found myself booking flights, hotels and such in Bitcoin (and paying the bitpay premium...*) because I couldn't be hassled to go through the bother of a credit card booking. Also find myself donating more often just because it's so easy... me and other people if you look around.
*looking forward for one of these services that pays some of their costs in Bitcoin and thus accepts Bitcoin to their own wallet. At least hosting you can pay in Bitcoin dammit!