I think the most shocking to me overall in terms of not seeing it coming was Phil Tufnell. He seemed to be motoring along quite happily, getting a decent public vote, being saved by the public regularly and then suddenly he dropped into the Bottom 2 from a decent leaderboard slot and was summarily axed over Ricky Groves, who was running on fumes at that point. I was also mildly surprised by Thom, just because he seemed to be at the beginning of a growth arc, but there was something in the air after his cha cha that suggested things were about to go south.
I'm never surprised when a pretty young woman is in the dance-off "shockingly". There's too much precedent, you always have to kind of be expecting it. Everyone and his dog on here has been predicting either Pixie or Frankie to be in the dance-off at some point around now from Week 1.
(I was also kind of surprised in a happy way when the public summarily booted Widdy, but that wasn't a dance-off situation)