OK! I just got the recorder back this morning, friday 8/10. I mailed it out UPS Ground on thursday 7/26(with an expected delivery date to them of wednesday 8/01). It cost $75 for the new internal battery, labor and return shipping. They fixed it and return shipped it UPS Ground back out to me this past monday, 8/6. Great turnaround time of only 15 days!
I had also mailed out the recorder from a UPS store, and had them package it, but M-Audio sent it back to me in a new Microtrack box with a new velvet black pouch for the recorder...very cool of them. +T to M-Audio!