I agree with almost everything COTN said, but to make my own points:
Dishonesty in a relationship, in all forms, is inexcusable. Whether or not it's "cheating" is a moot point because it's a deal breaker no matter what you call it.
As for the rest of the things on your list; it totally depends on the terms of the relationship. There are malicious and harmless forms of just about everything you mentioned. If you are honest with your partner, then I think flirting, dancing, sometimes even kissing, is not really that big of a deal. If you have an open or poly relationship, the list of what is acceptable is even broader.
If you (and I mean the general "you" here, not talking to anyone in particular) trust your partner and feel secure in your relationship, then honestly most of this stuff shouldn't matter. For example, if your sexual needs are being fulfilled then who really cares who looks at what porn? If I felt that I had to worry about any of this stuff, then I'd know the person wasn't right for me.