Everyone here is talking about iOMG, giving speculations and predicting what will happen, so I'll give my take, but I'm not going to try to create a plot or any of that, or go overboard in favor of any particular ship because that's not what I do. I'm instead going to just talk about what I saw in the promo and what I've picked up over time about Sam's character, since this is a very Sam-centric episode.
Sam always has been my favorite character in this show, and I feel all those who don't like her are misunderstanding her character completely. They say Sam is obnoxious and aggressive just to be obnoxious and agressive, or those who don't like her friendship with Freddie because of all the physical violence. Now I'm not going to go into the pedantic camp of those who say "she hits Freddie because she secretly likes him" because that's bull and anyone who believes that obviously needs to grow up and graduate elementary school. Since the beginning I've always seen the vulnerability in Sam's character, yes she is strong and confident but just like everyone else she has fears, insecurities and confusing thoughts. However she is so proud that she acts aggressive towards others to hide those fears. She's not a one dimensional character, and I love that iOMG is focusing on her emotions and insecurities that have largely been glossed over throught these 4 season (with a few exceptions of course)
Throughout the iOMG promo it was obvious that Sam was not herself, she had the same expression the whole time, she only said one word, "No", and she looked distant and troubled the whole way. Carly tries to help her by just telling her to talk to him and make a move because for her it's so easy, she's done it on multiple occasions (Griffin, Adam, Freddie, Shane) she gets what she wants. Sam is not that simple, she can't just ask someone out and just go for it, I mean when she liked Jonah she convinced Carly to have Freddie suggest to Jonah that he ask her out, she tries to change herself for Pete, she doesn't believe in herself enough to just go up and ask. However she goes to Freddie, or Freddie comes to her and gives her some very sound advice, and this exchange is the part were everyone is going crazy and thinking he's going to kiss him or he's going to kiss her, but I think that would actually hinder her development, it would spiral her more into confusion than before, and what she needs now is confidence. I think this episode is going to have great friendship development between Sam and Freddie, but a relationship would be not be beneficial for Sam at this point, a more developed, solid friendship with Freddie would though.