No Brittany/Sam physical interaction.
Rejoice! Sam is in every single scene on the McKinley side and he has some sort of separation anxiety RE: Brittany. He develops an alter ego who is smart and intellectual (Sam's "twin brother") and both (the two personalities). Yes, both personalities are in every glee club scene. He's not at the center of the storyline; He's just switching personalities while the other MHS stories take place. Sam's alter ego is presented as smart and handsome - he wears glasses, has a different hair style.
Brittany introduces the alter ego to other members of the club.
Everybody knows Brittany got admitted to MIT and they mentioned they are trying to get an early commitment from her so (I'm assuming) Sam's anxiety is coming from her going to Boston if she decides to go. It's not defined what she decides as it's an ongoing storyline.
Brittany talks about MIT with Tina, Brittany style.