certainly did NOT cartwheel or bits would be scattered down the runway. It seems that all passengers and crew have been accounted for with no fatalities.
The term "cartwheel" has different meanings to different people. Unfortunately, just like with the Boston Bombing, CNN rushed a story out without getting its facts straight, though at least this time it was somewhat more substantial than pure speculation.
At this time, it appears the plane's air speed was too low on final approach, and the pilot may have over-corrected by throttling up and then (mistakenly) putting the nose further up as a panic measure; This resulted in a severe tail strike on the sea wall, and the plane would have become aerodynamically unstable immediately after.
Typically in these scenarios, the plane (appears) to shoot upwards briefly due to the sudden change in weight distribution, and comes down on angled heavily to one side (having lost any ability to control lateral movement). The wing will typically sheer off, as they're actually designed to break away from the fuselage in such an event, and the plane will roll onto its roof then (if speed is high enough) or the nose will take a digger, break off, and the whole thing will flip in the air and then promptly "face plant" in the dirt in one piece.
Either way, the plane did exactly what it was designed to do -- separate the flammables from the fuselage where the passengers were, and maintain integrity until all motion stops. The emergency crew's prompt response is what saved everyone's lives -- most people don't die due to the impact or fire, but rather smoke inhalation.
This is a text-book crash landing, and the investigation will now focus on whether a mechanical fault caused the plane to lose speed at the last moment (bird strike on engine is common), or whether the pilot neglected to flare correctly. Judging by the debris, it looks like it would have been a steep descent with flare at the end -- which results in a faster landing and is preferred at high-volume airports, over a shallower approach, with less flare. If the pilot is inexperienced, distracted, or any number of a dozen other things go wrong (one plane crash I know of was due to a circuit breaker trip-out which meant the captain did not have 'stick shake' or stall alarm warnings in this exact scenario) -- there's very little time to react, and even going to full power take off speed will not prevent disaster due to the steep descent angle, lack of altitude, and lack of speed.
Any airplane pilot knows the key to a successful crash landing is speed and altitude -- they add precious seconds to react to an emergency. This plane had neither.