A theft of names and email addresses like the recent one from marketing firm Epsilon doesn't sound that bad but that information is valuable for scammers to use in further attacks, notably in phishing scams.
If an attacker knows your name, the companies you deal with and your email, then it can craft some convincing emails that have a much better chance of fooling you.
ZDNet Australia's Darren Pauli presents some fabricated examples of phishing emails to illustrate what users need to watch out for in order to protect themselves.
The first one from Disney has mass appeal. The broad list of victims could be attractive for scammers.