Tivo actually sent a message warning people whose Season Passes were set to record beyond the scheduled time that if they left it that way it wouldn't record right, but the opposite happened in that when I set it to their time I did not get the end of the show recorded. I think NBC did that on purpose so they could sell more DVDs and not have people passing around copies of the episode!!!
Fortunately I also have a Season Pass for ER, so I got the end of the Friends episode on the ER recording (although it did not record all of ER, which obviously went over into the news -- I didn't think they'd do that. Did Abby show up for her graduation?