Now the fly in the ointment. Some DVR's won't pick up the last few minutes. You might want to call your cable company and see if this will be a problem. Better yet, watch it live. Let us know what moments you're the most excited to see. Valar Morghulis!
DVRs would only screw up if the guide data is wrong. And there is no reason to suspect it would be wrong since this 70 minute episode is the officially announced run time.
Maybe I'm missing something.
PS: I'm not knocking your post. Head's up are always good to have. It's just the zap2it comment.