1btc coins sold out. I've also reduced the price for the 100 btc bar. And I can also sell that bar redeemed for 2 btc if there's any interest.
The bar has a error series 1 hologram. There's only 130 of these bars ever made: http://casascius.appspot.com/group?type=3
Out of those 130, it looks like there are only 57 bars that have the rare series 1 hologram like this one. It's truly a collector's item.

I also figured out how rare BitBills are:
20BTC: 181 (132 intact)
10BTC: 143 (97 intact)
5BTC: 144 (107 intact)
1BTC: 589 (492 intact)