The 'Mac Guy' was what some marketing person thought would appeal to the commercials target audience.
The PC character was intended to represent the 'WinTel' computers as the 'stuffy' prim and proper 'adult' type computer, and the Mac character was intended to represent the Mac as the young, 'hip', easy going, and perhaps most importantly, trendy computer.
In short, the ads were targeted to appeal to the new office culture where everyday is casual day.. where a jacket and tie isn't a requirement, as well as typical high school and college students.
It seems to have been an effective campaign, if the numerous parodies are any indication.. but Apple would be well advised to end that series of commercials while they're at their peak, and not drag them out for another dozen or more 'episodes'.
A 30 second spot isn't nearly enough time to demo the OS, or go into any great detail about the technical differences between Mac's and PC's as some have suggested.
No.. think of all the commercials that people still remember decades later.. like the 'Wheres the Beef?!' lady from the Wendys commercials.
An effective commercial gives the perspective customer just enough information to wet their proverbial appetite and encourages them to investigate the subject further.. generally by getting a catch phrase related to the product stuck in their head.
Head on.. apply directly to the forehead! Head on.. apply directly to th forehead!
Or in Apples case.. 'Hi. I'm a Mac. And i'm a PC".
The problem with Apples 'Think Different' campaign is that while most people like to think that they 'Think Different'.. not many people want to BE different.
I mean, really.. think about how consumer trends work. A person sees another person driving a cool SUV thing, or wearing a flannel shirt, and next thing you know, L.L. Bean is selling record numbers and Ford can't build SUV's fast enough.
It's probably the main reason 'MacAddict' is changing its name.. since Apple in general (especially since the commercial success of the iPod) is trying to shake that long standing public belief that Mac users are quirky, strange artsy type people.
Which is why the 'get a mac' commercials tapped a young, hip, everyday 18 to 34 year old to play the role of 'Mac'.