omniscient
Third person limited is far and away the most common method for writing novels. I think it was in 1990 or 1991 that Publisher's Weekly reported that just over 90% of all current novels were written in third person limited. This has dropped some, but not a great deal.
Most of the rest were divided between first person and omniscient, with a smattering of second person and objective or dramatic POV.
I've never heard it called third person shifting or rotating. This sounds like third person limited, multiple viewpoint, to me. It's generally used in long, saga type novels, though it can be used in shorter novels.
It's still just third person limited. Third person limited has no limit on the number of characters you can use, it just means you only get inside the head of one character per scene. When the scene or chapter changes, you're free to get inside someone else's head. But whether you're using only one POV character, or fifty POV characters, it's still just third person limited, as long as you only get inside the head of one character per scene or chapter.
Omniscient just means you get inside anyone's head anytime you wish, whether it's in the same scene or not. I do think third person limited should be mastered before tackling omniscient. I'm not sure third person limited is really any more difficult than omniscient, but it is what most editors want from new writers, and it is what most readers prefer reading.
If you just jump into a secondary character's head within the same scene now and then, it's called head-hopping, and it makes for bad writing. Consistency really separates head-hopping from omniscient.
Personally, I'd like to see more novels and short stories written using objective viewpoint, but not many seem to know what this is these days.
Generally speaking, it's a bad idea to withhold information the POV character knows. If he or she knows it, the reader should know it, as well. This is the main reason Doyle used Watson as the POV character, rather than using Holmes. The reader doesn't necessarily have to know he knows it, but it should be there, if he's smart enough to see it.