Sorry for my ignorance, but has this issue been resolved on BC.I's end?
Yes, there haven't been any bad transactions for a week now.
There are still people paying to addresses that were exposed by the bug or that were created by the buggy random number generator, but there is nothing BC.I can do about this.
Edit: I should add that bc.i claimed to fix this bug within a few hours. There is no way to prove this from my end, but the logs support this as more than 75% of the bad transactions occurred during a few hours.
BC.I has changed to RFC 6979, now. Thus, the signatures do not depend on the random number generator anymore.
It sounds like it is somewhat safe to use blockchain.info again.
I would also say this just shows the importance of rigorously testing any new release of any software that in any way controls any kind of money because people may not immediately continue the upgrade cycle after a 2nd release is released to fix any potential problem