I have been rendering 28:30 tv episodes in NTSC DV AVI Default Template for almost three seasons now. Every file is roughly 6.8 to 7 gigs. Last night i hit render again with same settings on a file that had been previously rendered and the file size is 72gigs.... Whats up?

No forgotten clip 50 minutes down the timeline
only change was audio track (narration) delivered from miniDV

No forgotten clip 50 minutes down the timeline

Are you positive?
Hit the Go to End button and confirm that it does indeed stop where it's supposed to.
If it does, then my next suspicion is that you accidentally rendered it as uncompressed.

Also, is it possible you rendered to Uncompressed instead of DV?