Second Interview for The Apple Store?

I recently went on an interview for the apple store, the person who interviewed me said he was impressed and that I nailed it. At the end of the interview he said he would forward my name to the hiring manager and he'll be in contact with me in 2-3 days. I was interviewed on Monday, it's now Thursday. Should I wait it out and assume I didn't get the 2nd interview or should I call them up and ask? If I call what do I say, I don't want to sound like I'm desperate even though I am. Please help.

Thanks for all the great answers you guys! They called me today and scheduled an interview for tomorrow.

You should call back ASAP and ask where they are in process. Example:

"I enjoyed the interview with you earlier this week. My interest in working for The Apple Store is great and I'm looking forward to hearing from the hiring manager. Can you tell me where you are in the process. I wouldn't want to miss the opportunity to speak with them."

Then let them do the talking.

I would call, and just be confident and professional. It won't hurt to speak with the individual that interviewed you and touch bases with him. I would start there. They also may take a bit longer than you are expecting to get back to you. I know you'll do great wherever you work, all the best to you!!

Give them a call today or tomorrow, asking how the process is going. That's open ended enough for them to say that they're still interviewing applicants.