I recently ordered some bitbill.com cards in the mail and they have arrived! Wahoo! I ordered each type of bitbill (1, 5, 10, and 20 BTC) but they all didn't arrive yet so hopefully the rest will arrive soon. I only got the 1 BTC bitbills as of now.
So what did I think of them? Well, they looked just like what I had ordered, however, the cards themselves don't have the feel of credit cards. The material is not as strong as a conventional credit card. There seems to be a thin piece of plastic sandwiched between two sheets of clear plastic. When you rub your thumb over the hologram it is raised so there is definitely something under there. The private-key-QR-Code is an actual piece of paper under the hologram. The larger public-key-QR-Code looks like it was printed on the card since I could not feel the bump using my thumb. The circular hologram on the front is some type of metal foil that rests on top of the QR Code. The rectangular hologram on the back is also raised. The hologram on the back says "AUTHENTIC", "GENUINE", "VALID", and "SECURITY", and the front hologram has a globe that has the words, "SECURE".
The edges of the bitbill look like they have been cut with minute fraying on the edges. The cards still look pretty cool though, and it does say "beta" on it. I expect bitbills.com to make the cards even better in the near future, but this is a good beta.
I have an Android smart phone and I used an app named Google Googles to take a picture of the public-key-QR-code on the back of the card. Google Googles was able to successfully convert the public-key-QR-Code into a bitcoin address. I entered the key into blockexplorer.com to verify if there was 1 BTC on the card, and I am happy to say there was. :-)
I do not think it is possible to remove the hologram on top of the private key QR Code without significantly destroying the card. In the next few days I will be attempting to remove the private key QR Code without destroying the card. This is just a test of the card and I do not have malicious intent. :-)