I have never used this service and from reading what it does, I probably never will. BUT, if were the kind of person into these type of things, I would feel pretty good about them. The explanation sounds sincere, honest and heart-felt. They have done their research and discovered what caused the problem. The credit card numbers were only in the source-code of the HTML, not actually diaplayed on the HTML page (I know it only takes 2 clicks to see the source, but how many people check out the source code of every page we see through the day ?). And they are telling us that they are well-funded to dedicate more resources on security. I feel pretty good about them.
I'm pretty sure there are much easier ways to get credit cards online than randomly looking at webpages. Can't you buy them in bushels from Romanian hackers? I hear the going rate is much less than a dollar a number.*
*I hear this from a person who used to work in e-commerce stopping illegitimate transactions, not from illegal activity, btw.
Credit card numbers alone can be generated, no need to steal them. Only in combination with the expiry date and cvv do they have any value, newer cards are protected with a pin code for that reason.
The whole reason the VBV program exists is to make the numbers alone worthless.
Why would you single out the Romanians?, there are people doing that sort of thing all over the world.