Continuity mistake: In "iGo to Japan", when the iCarly crew, Spencer and Freddie's mom have to jump out of the airplane, Freddie's mom jumps out of the airplane with out buckling the parachute backpack in a rush to follow Freddie. But when everyone has landed, she is struggling to unbuckle and take off the backpack.
Continuity mistake: In "iGetPranky", when Carly and Spencer begin talking, Carly turns off the TV before they start talking. Then she turns off the TV once again.
Continuity mistake: Whenever they are doing the show, Freddy is almost always holding the large camera with blue light. When it shows him holding it, it's shaking. When it shows Carly and Sam from the angle of Freddy's cam, it is perfectly still. Always.
Continuity mistake: In some episodes, Lewbert's wart is small or not even there.
Continuity mistake: When Freddie holds his camera to film the web-show, he holds it at chest height pointing the camera upward to film the faces of Carly and Sam, but when you see footage from Freddie's camera it is completely straight.
Chosen answer: I don't know how to answer the first question but for your second question, there is going to be an episode after iPWV, called IDate Sam & Freddie which will deal with their kiss from iOMG. IParty with Victorious will not be related to IDate Sam & Freddie.
The I date Sam and Freddie proves that they are a couple.