I didn't want to stress you out before your interview, but now that you've got the job, I'll go ahead and say it. Fry's is known for their horrible customer service. Beyond bad. Google "Fry's" and you'll see what some people have to say about it. I know that every company has its detractors, but Fry's does appear to be one of the worst electronics retailers in terms of customer service.
That said, they need people like you to turn things around. Congratulations on the job. Now go out there and be courteous, be knowledgeable, and be helpful. In the fast-changing world of electronics, people like this are desperately needed. It's not just another retail job...take pride in what you do, educate yourself, and share that education effectively with others. As a Mac person, you're fully aware of the "evangelist" role Mac owners often play. Now you're expected to do that across the board in order to help people find what best suits their needs. Best of luck to you...I'm looking forward to hearing about how Fry's has turned things around to become the shining beacon of electronic retail. 😀