I've checked into Jonah Hill not appearing on last week's Raw Supershow and apparently he was never scheduled to appear live. Hill taped segments for WWE television but they were scrapped in last minute re-writes.
Things are changing more frequently than ever from a creative standpoint in WWE. In addition to Hill's guest appearance being scrapped, Triple H was scheduled to appear (and locally advertised), there were plans for Brodus Clay to debut and going into Survivor Series on Sunday there were no plans to break up the team of Awesome Truth.
A possible reason for some of the dysfunction is Vince McMahon keeping stuff close to his vest and not cluing the creative team in on his plans until the last minute. Mondays are always stressful for the creative team as they try to finalize the script that effectively progresses storylines and fits into their time window. As a result, things that are planned (and sometimes even advertised) are cut out. A segment that was recently bumped several times is the Michael Cole/Jim Ross challenge.