1. Security researchers, so they can see what malware may be lurking in FPGA bitstreams.
2. Open source developers working on FPGA bitstream compilers.
3. People who want to steal proprietary IP cores.
It hurts:
1. People who chose the part because of the closed bitstream particularly. In part because they made security decisions that the bitstream wasn't open.
2. Anyone who bought the products based upon the marketed security claims of the product (Hopitals/DoD/etc)