Some smashing images posted! Thanks to all. 
I must admit, as only a recent initiate into the wonderful world of photography I don't have the kind of knowledge that you guys do in terms of composition or technical skill involved in taking these shots, so I can only judge what I see and how it makes me feel.
I apologise in advance if my summary below is not up to your usual standards, I have mostly refrained from any technical or artistic critique, (although a little crept in) but rather explained what I saw and what emotion it invoked in me! The winner had to be the one that amused me the most...
I was tempted to use Queen Vic's famous quote, 'We are not amused' but this certainly does not apply to any of the images posted... 
Mike325
An amazing moment in time captured as the chap somersaulted over, (I'm guessing) members of the crowd, one of those shots where you have to be in the right place at the exactly the right time to capture and you've nailed it! I'm impressed!
TustinMike
It took me while to work out exactly what was going on here, your image intrigued me. I love the framing and the perfect depth of field / shutter speed relationship to capture the action and provide the blur that adds so much to the shot - love it!
ejrj6586
Excellent shot of the anticipation that riding something like that would involve - the positioning is spot on and the amusement on the children's faces is clear - they are certainly enjoying themselves! Your shot made me look at the kids and examine how I think each one was feeling, I would definitely be the sensible kid, at the back and with my coat on, hood up, looking slightly more apprehensive than his mates at the front!
Scatterbrained
This is a stand out shot for me, the angle of the framing is perfectly matched by the angle of the roller coaster as it turns that bend - in what must have been a challenging environment. Looking at the image I can hear the 'whoop' and screams from the front of the train(?) and see the arms being flung up in air in my minds eye. Considering the shot is of the back of peoples heads it really conveys their emotions to me. But interestingly, the emotion I really get strongly from the chap on the left of frame is anxiety - he doesn't appear to be very comfortable or enjoying himself! (This is not a criticism of the shot, far from it - it invoked strong similar feelings in me, exactly how a great photo should, in my humble opinion.)
CameronCorner
Lovely representation of a family out having a great time - they certainly look amused by the clown contraption. To my eye the colours are very vibrant without being over saturated and again I love how you have framed it with the perspective leading into the image - and how you have captured the concentration on the children's faces - it is a great shot.
Maureen Souza
Everything about this shot amuses me! The antlers, the expression on the dogs face, how he is looking out of the frame, how his ears are folded over his head helping to secure the head dress. The depth of field is great, separating the main subject from the background, where the tree lights provide smashing bokeh.
Alan_Potter
Alan - you certainly managed to invoke many happy memories for me! I was amused every Christmas by pantomime put on by the local AmDram society in the small Somerset village I was brought up in - I don't think I'll ever forget seeing my Father parading around the stage dressed as an ugly Sister! The shot itself is great, very well timed and 'describes' the fun and childhood excitement perfectly - as with some of the other shots above, I can hear the 'chef' shouting to the crowd in the classic call and response manner - it makes me want to shout 'he's behind you!'
It was very difficult to pick a winner, each one is truly worthy and I suspect that seven different people could easily pick seven different winners, but for me there were three contenders that I flipped back and forth between...
Maureen - your shot made me laugh out loud.
Scatterbrained - yours is my favorite shot posted and invoked the most emotion - although not amusement!
Alan - in the end I couldn't ignore the pleasure and amusing memories that your shot brought flooding in - you are my winner!
Thanks again to all and best wishes,
Rob
The aim is to show improvement as you scroll down!
