카메라가 회전했는데도 fingerPos 값은 이전 벡터의 방향 그대로여서 나타나는 문제 같습니다. OnMyFingerDragMove 함수에서 tempFingerPos 벡터를 카메라가 회전한 만큼 회전 시킨 다음 그 값을 적용해 보기 바랍니다.

test.cs

using UnityEngine;
using System.Collections;


public class PickupAndMove : MonoBehaviour 
{
	public GameObject targetObject;
	public GameObject noTargetObject; // 선택하면 안되는 오브젝트(테이블).

	private int dragFingerIndex = -1;
	Rigidbody tempRigbody;

	void OnEnable()
	{
		FingerGestures.OnFingerTap += OnMyFingerTap;
		FingerGestures.OnFingerDragBegin += OnMyFingerDragBegin;
		FingerGestures.OnFingerDragMove += OnMyFingerDragMove;
		FingerGestures.OnFingerDragEnd += OnMyFingerDragEnd;
	}

	void OnDisable()
	{
		FingerGestures.OnFingerTap -= OnMyFingerTap;
		FingerGestures.OnFingerDragBegin -= OnMyFingerDragBegin;
		FingerGestures.OnFingerDragMove -= OnMyFingerDragMove;
		FingerGestures.OnFingerDragEnd -= OnMyFingerDragEnd;		
	}

	void OnMyFingerTap ( int fingerIndex, Vector2 fingerPos, int tapCount ) // 클릭 오브젝트 확인용.
	{
		GameObject selection = PickObject(fingerPos);
    
		if(selection != null)
		{
			Debug.Log ("Your Select Object = " + selection.name);
		}

		Debug.Log ("Finger Position = " + GetTestPos(fingerPos));
	}

	void OnMyFingerDragBegin ( int fingerIndex, Vector2 fingerPos, Vector2 startPos )
	{
		GameObject selection = PickObject (fingerPos);	

		if(selection != null && selection != noTargetObject)
		{
			targetObject = selection;
		
			dragFingerIndex = fingerIndex;

			tempRigbody = targetObject.GetComponent<Rigidbody>();
			tempRigbody.useGravity = false;
			tempRigbody.constraints = RigidbodyConstraints.FreezeAll;

			Debug.Log ("PickUP Object : " + targetObject.name);
		}
	}

	void OnMyFingerDragMove ( int fingerIndex, Vector2 fingerPos, Vector2 delta )
	{
		if(dragFingerIndex == fingerIndex)
		{
			Vector3 tempFingerPos = GetWorldPos(fingerPos); 
			tempFingerPos.z = targetObject.transform.position.z; // z를 오브젝트 좌표로 고정한다.
		
			if(tempFingerPos.y < 0.151f) tempFingerPos.y = 0.151f; // 테이블 밑으로 못내려가게 한다.
 
                        // 여기에서 tempFingerPos 벡터를 카메라가 회전한만큼 회전시킨 다음에 
                        // targetObject.transform.position 값을 변경해 보기 바랍니다. 
                        
                        // 예) 90도 회전한 경우 
                        // tempFingerPos = Quaternion.Euler(0f, 90f, 0f) * tempFingerPos;
      
			targetObject.transform.position = tempFingerPos;

			Debug.Log ("Moving Object : " + targetObject.name);
		}

	}

	void OnMyFingerDragEnd ( int fingerIndex, Vector2 fingerPos )
	{
		if(dragFingerIndex == fingerIndex)
		{

			dragFingerIndex = -1; 

			tempRigbody.useGravity = true;
			tempRigbody.constraints = RigidbodyConstraints.None;

			Debug.Log ("Release Object : " + targetObject.name);
		}
	}	

  public static GameObject PickObject( Vector2 screenPos )
  {
        Ray ray = Camera.main.ScreenPointToRay( screenPos );
        RaycastHit hit;

        if( Physics.Raycast( ray, out hit ) )
            return hit.collider.gameObject;

        return null;
    }

    public static Vector3 GetWorldPos( Vector2 screenPos )
    {
        Ray ray = Camera.main.ScreenPointToRay( screenPos );

        // we solve for intersection with z = 0 plane
        float t = -ray.origin.z / ray.direction.z;

        return ray.GetPoint( t );
    }

}