Ok a quick summer up to this point. All hell is breaking loose Dean and Sam have a brother named Adam who is now the new vessel for Michael.
Ok this week we find out a major twist in the whole Apocalypse thing. Their are hundreds of Gods running around and the one they are looking is just one of them since their is so many religions. The brothers get basically kidnapped by Kali, Ganesh, Mercury, Zao Shen, Odin, and Baldur. A nice exchange is made between Odin and Zao-Shen about how his Wold carring turtle is more realistic then his huge snake eatting him.
Gabriel Shows up and gets killed by Lucifer.
We find out that even thoe the brothers cant kill Lucifer they can trap him but the need the four keys to do it. and what are thoes keys? the Horseman rings of course. Cue the plot for the next 3 episodes Find and Kill Death and Pestilence
Good episode I love that they brought in the rest of the gods and how they are all bitchy about who should have the right to end the world seeing as they were there long before the God they are looking forwas.
The Apocalypse had seemed like the perfect way to end this series (since it had been widely rumored before March that it was a five-seasons-and-out deal for the creator and 2 main actors). I'm stoked that Supernatural is coming back for Season 6, because the Apocalypse storyline just gets more and more awesome as Season 5 progresses.
Losing Loki/Gabriel hurts - the Trickster episodes were always great, and it was a nice revelation that Castiel hasn't been the only angel on the humans' side. With 3 episodes left in this season, it's going to be interesting to see if Sam & Dean are able to get Death & Pestilence's rings before the season ends - or if we get another twist that pushes that to next season. I can't see a full season dedicated to trying to trap Lucifer.
Friday is going to be lower than M-Th, because less people watch TV on Friday. And a new show will usually lose about 25 to 30% of its viewers after the premiere. Leno actually fell 40% from Monday to Tuesday.