I think itīs fair to say that if you are about to fly your third sector in as many days as a passenger in a B737-400, you're probably as aware of the drills as you're ever going to be! Enough repetitions commit the briefing to memory (it's what we do as pilots with our emergency brief etc.).
I listen and look at the cabin crew out of respect for them and their job, but to be frank I don't need to. However, I do read the card and check out the location of the exits as I board. I also know how to work the seat belt buckle as it's identical to the ones on my 1969 MG!