After reading articles about seized bitcoins, I can't help but think about all those other digital assets floating around that could be valuable: Eve Online spaceships and Plex, prepaid years of service (Dropbox plans are $99 and up)...
Protip: Always store your Bitcoin private keys on multiple locations. I don't think the DEA has moved the bitcoins itself, they most like just took the harddrive with the wallet on it.