Is my southern accent a hinderance for my app demo video? (onsitetimetracker.com)

I have no problem with the accent, but you might want to write out your copy and repeatedly practice the delivery for maximum effect. The time tracker looks good... congrats.

I won't lie, it does sound unusual. However, Cf Cilk http://www.youtube.com/watch?v=MDexbD06iyM. Their video is narrated by someone from New Yawk, who may have been in My Cousin Vinny. He also has the worst haircut I have ever seen in my life.

You sound just fine. Practice more, get rid of the "uh"s and "um"s, and you'll sound great.