A general remark
As a person who once wrote a program to spoof email addresses, and also time (hehe, I can go back in time now :D), for fun and to learn socket programming, I was always wondering, why do we use such a retarded protocol as SMTP for sending emails? Or, better put, why do companies trust the email headers?
It has so many obvious flaws, and is extremely insecure and vulnerable to faking. You can type whatever you want in the from: field (and all the others!), yet so many companies and individuals (I'm speaking from my own experience) blindly trust whatever their highly secure Outlook (or another) client displays.
Another point, don't people remember? .doc, .xls, and the like have been proven insecure many, many, many times. Especially macros. I really don't get why people come back whining if they get "hacked" after they use such formats.
This just uses human stupidity, as do most of today's attacks; therefore, it does not fall into the category of sophisticated attacks. Certainly, it is centered on only one company/individual, so it is harder to detected, but the principle stays the same. Saying that this is sophisticated is pretty much the same as saying that you are a more sophisticated pickpocket if you steal only one person's wallet since there is less chance you'll get detected (ok, stupid analogy, but I couldn't think of anything else right now).