There are some things you should know to enjoy this episode even more - and I'm sharing them because not all fans may know this stuff (unless you watch some of the convention clips on YouTube like I do).
First of all - yes - there are Supernatural Conventions - and a magazine. They've even won at least one award (which will show up in the show).
Secondly - for at least part of one season - Jensen (Dean) did live with Jared (Sam). I don't remember the whole story - Jared owned a house and the place Jensen had been renting wasn't available or something....so they decided to share Jared's house (for at least 7 1/2 episodes at the point I watched).
Third - Jared/Sam really is married to Genevieve Cortese (the second Ruby - with dark hair) - they will be celebrating their 1st anniversary this coming weekend.
Fourth - I'm thinking that something in the show is there because at a convention one of the boys probably said something like, "If they can find a way to put an alpaca in the script - they will."
Fifth - Jensen/Dean really WAS a soap opera actor and played "Eric Brady" on Days of Our Lives for a while...
Six - I don't know how it is used - but you'll see a gold goblet/chalice that was used by Meg (and others) to contact "Father" (with blood). In case you haven't seen prior episodes...that is what they're pointing to.
Seven - Misha Collins (Castiel) really does tweet...and wear goofy sweaters. When the show was up for "TV Guide cover" contest where the viewers voted for the cover (and the show won) - Misha was tweeting the fans all the time telling them to vote, etc. (He says in interviews that if he could only tweet and tell them to "rob banks for us" - then he'd be successful).
That's all I can think of - but there are jokes, etc. in this episode that if you're not familiar with the show you might be going "huh"?
Oh - and the reviewers I've read so far - all LOVE this show and say its better than "Mystery Spot" (where Dean dies several times) and "Changing Channels" (where they spoof cop shows and hospital shows and game shows, etc).
Ok....enough jabbering. I can just hardly wait till tomorrow night.....(we don't get cw - so Robin downloads it via. "torrent" or something like that - starting a few minutes after the show ends).