I thought the central theme was connection. The story is about a brief period of intimacy between two lonely characters who are unaccustomed to such closeness. Wallace is intensely aware of his loneliness because his success aggravates it and because of his past history with depression. It's not clear to what extent Lipsky is aware of his own loneliness until the end of the script where he says, "David thought books existed to stop you from feeling lonely. If I could, I'd say to David that living those dos with him reminded me of what life is like -- instead of being a relief from it...and I'd tell him it made me feel much less alone." The characters are able to connect because they find themselves in a situation where they each need the other's approval and are willing to be open and vulnerable to obtain it. I think one of the sub-themes is envy. Lipsky envies Wallace's talent and success. Wallace envies Lipsky's ability to live vicariously through Wallace on the tour, then return home without having to deal with the emotional aftermath. Their mutual envy creates both closeness and distance in their relationship at various points in the story.

Rashonda, again some excellent observations. I concur Connection is a key theme. It's something Wallace keeps coming back to, his rants about contemporary culture and especially technology putting into peril. Also I think one of his fears about his imminent fame is being thrust into a world in which he would be unable to determine if any of his connections where authentic or whether people were responding to him based solely on his name. Re envy: That is definitely in play, overtly via Lipsky, but also, as you note, from Wallace toward Lipskay, in particular the ease with which he interacts with others socially, Wallace much more awkward.