Unahim wrote:
Mishaps only happen if the position would make the unit unable to move there. That's not the case for the Skimmer, so even though the mishap comes before the move is concluded, that's no problem here. There will be no mishap, since the position is legal for the Skimmer.

Deep Strike Mishap: If any of the models in a Deep Striking unit cannot be deployed...on top or within 1" of an enemy model, something has gone wrong. The controlling player must roll on the Deep Strike Mishap table and apply the results.

Skimmers: If a Skimmer is forced to end its move over friendly or enemy models, move the Skimmer the minimum distance so that no models are left underneath it.

Zimko wrote:

A Deep Striking model counts as having moved after it arrives but you must complete the Deep Strike before the model has arrived. Mishap is part of Deep Striking and is triggered before the unit arrives and therefore before the unit is considered to have been moved.

Deployment via Deep Strike (and thus mishaps) is before the Skimmer rule triggers.

Skimmers :

MOVING SKIMMERS
Skimmers can move over friendly and enemy models, but they cannot end their move on top of either.
Skimmers can move over all terrain, ignoring all penalties for difficult terrain and Dangerous Terrain tests . However, if a moving Skimmer starts or ends its move in difficult or dangerous terrain, it must take a Dangerous Terrain test. A Skimmer can even end its move over impassable terrain if it is possible to actually place the model on top of it, but if it does so it must take a Dangerous Terrain test.
If a Skimmer is forced to end its move over friendly or enemy models, move the Skimmer the minimum distance so that no models are left underneath it.



And the actual rules for Mishap and Deep strike verbatim

Arriving by Deep Strike
Roll for the arrival of all Deep Striking units as specified in the rules for Reserves and then deploy them as follows:
• • First, place one model from the unit anywhere on the table, in the position where you would like it to arrive, and roll for scatter to determine the model’s final position. If a vehicle scatters when arriving via Deep Strike, do not change its facing – it must continue to face the same direction as it did before you rolled for scatter.
• • Next, the unit’s remaining models are arranged around the first one. Models must be placed in base contact with the first model and begin to form a circle around it. When the first circle is complete, a further concentric circle must be placed with each model touching the circle inside it. Each circle must include as many models as will fit.
• • Models deploying via Deep Strike treat all difficult terrain as dangerous terrain.
In the Movement phase during which they arrive, Deep Striking units may not move any further, other than to disembark from a Deep Striking Transport vehicle if they are in one.

The actual mishap rules

Deep Strike Mishaps
Deep Striking onto a crowded battlefield can be dangerous, as one may miss the intended objective or even materialise inside solid rock! If any of the models in a Deep Striking unit cannot be deployed, because at least one model would land partially or fully off the table, in impassable terrain, on top of a friendly model, or on top of or within 1" of an enemy model, something has gone wrong. The controlling player must roll on the Deep Strike Mishap table and apply the results. If the unfortunate unit is also a Transport, the Deep Strike Mishap result applies to both the unit and anything embarked within it.

deevil wrote:
This thread and the deepstriking+tank shocking skimmers, wwp+fortifications should learn from each other...

Assuming the DS is not movement; dangerous terrain means nothing to the deepstriking Skimmer or unit, unless it goes flat out or models disembark from it. Same is true for models, not skimmers, that run after being placed.

Assuming DS is movement, WWP+fortifications would probably work, tank shocking skimmer will definately work...

It just comes down to what kind of world you want to live in...