Wow! This is a tough one to answer. As in all things poker, it depends on the circumstances.
For instance when Tiffany Michelle called the clock on they guy, he was trying to make a decision for his tournament life. Of course, with footage being edited, we really don't know how long he actually took. The other players at the table gave differing accounts as to how long he had taken before the clock was called, but none of them felt it was necessary for someone not in the hand to call the clock on him. Of course Tiffany Michelle justified it by saying she was short stacked. In fact, she had over 50 big blinds. While not a chip leader, I don't think that would be considered short stacked.
In the Negreanu hand shown above, it seems pretty outrageous to call the clock on someone after less than a minute has elapsed. It was so fast that it wasn't even clear to Daniel as to whether someone is actually allowed to call the clock on that fast. I'm not going to look it up in the WSOP rules right now. But off the top of my head, I'd say there is nothing stopping him from doing it. But you have to be careful about doing something like that. I heard a story a couple of years back. I don't remember if the guy who was telling it was the one who actually involved, or if he was just one of the players at the table when it happened. I wish I could remember who the players were. But the story goes that one guy calls the clock on the other guy, who didn't feel he had taken an unreasonable amount of time. The player whom the clock had been called on retaliated by calling the clock on the other player every single time action was on him. As soon as the player in front of the guy had acted he would just say "clock".
Then you have players like Yevgeniy Timoshenko, who, if we were being polite, would be described as deliberate. If we're weren't, we would say he plays slow as hell all the time, so much so that it prompted Annette Obrestad to call the clock on him after only a couple of minutes, in a hand that she wasn't involved in. In this case Timoshenko wasn't facing a bet. In fact he was holding a full house and action had been checked to him on the river. But with Timoshenko taking so long to act on every street, the hand had already taken so long that it was necessary to take a commercial break and come back to see the conclusion. Annette Obrestad was fed up and called the clock on him, and I don't really blame her. Timoshenko plays excruciatingly slow all the time. Seriously, it shouldn't take you five minutes to figure out how much to bet on the river with the nuts. Maybe to call, but not to bet. He didn't think it was cool of Annette. Annette wanted to see more hands. And again, I don't blame her. As she put it, he always takes an absurd amount of time.
So is it right? Is it rude? It depends on the situation and the circumstances. Obviously, someone might need to take a little more time when facing a big bet or an all-in. And of course a player should probably always take a little time to consider his hand, the board, the action in front of him, and weigh his options. Take a little time, not a lot. There is no need to Hollywood for the cameras. I know when your bluff gets raised you don't want to fold too fast, so it's not so obvious that you had complete air. But let's not go overboard. Like Tony G says, you can play ten tables at a time and make decisions in less than 30 seconds, and now it takes you five minutes to make every single decision. "Don't waste my time!" It may be rude for someone not involved in a hand to call the clock. But I think it's just as rude hold the game up.
If nothing else, respect the game.