Yeah, it looks really interesting, but not as a competitor to Bitcoin, but as a complementary technology. It reminds me a lot of Open Transactions.
Voucher-safe isn't a distributed store of value, it's a distributed representation of the store of value. You still need a trusted issuer (or many of them) for the vouchers. These issuers in turn could store the value in gold, in bitcoin, or in anything else. Of course bitcoin has huge advantages here as it would enable anybody in the world to audit the issuer and keep them honest, and would save them huge sums of money on vaults, guards and transfer costs.
It adds a few advantages to the bitcoin system alone: real, built-in anonymity; instant guaranteed payment; a choice of different backing value stores.