I just learnt about the BGP attack:
The attacker was able to redirect the miners to its own pool to effectively "steal" (defraud them of) their mining rewards.
I don't know enough about the Border Gateway Protocol, but I'm wondering if this sort of an attack could be used to split the Bitcoin network itself, essentially by hijacking the node discovery process. If an attacker could hold the split for a few hours (assuming enough hash power), it could successfully execute a double-spend on its target.
Does the client use any kind of authentication with its peers?
P.S. Of course, there would have to be enough economic or political motivation to carry out such an expensive attack (such as to bring down a popular exchange and create media panic).