I have never seen two brands of cars that I couldn't distinguish in a second or two, any double-takes notwithstanding. It would not take me a minute. Nor have I seen two models of cars that were slavish copies. When the day comes that all tablets look almost exactly like iPads, and our brains have adapted to telling the brands apart from whatever subtle differences they possess, you might have a point. In the meantime, Samsung is clearly trying to sell their tablets based on making them as indistinguishable from an iPad as they can get away with making them.
I don't see how anyone can support this business model. If they were an honest company, they would market their tablet on its own merits, not on how much they can cause brand confusion, or on how closely they can mimic another company's design.
I'm not interested in defending Samsung here, but I do agree with the posters upthread that Apple's actions do show a certain amount of insecurity. Again - did Mercedes-Benz or Jaguar say anything about the Amanti?
Certain cars have a very distinctive look, and intentionally so. If another company were to try to make a car that slavishly tried to copy their distinctive look, then I think the first car company would have every right to sue the second car company. E.g., if another company were to make a car that would take you a minute to notice the difference between it and a Nissan Cube, then Nissan would be well within its rights to sue.
On other other hand, some cars are made to look "just like every other car". Clearly for the cars that are doing this, there is nothing to sue about.
The Jaguar has a very distinctive front-grill. The rest of the car is less unique, but if someone were to copy the Jaguar down to the front grill, then Jaguar should sue.
The Mercedes is not very distinctive to my eye, other than the prominent round Mercedes ornament on the hood. If another car company were to make a luxurious-looking car with a round peace-sign ornament, for instance, on its hood, then Mercedes should sue.
As to whether car companies sue each other in practice, I have no idea. I'm sure they would, however, if they felt that (1) another car company were making a slavish copy of their design, (2) they had a good chance of winning the court case, and (3) the suit wouldn't somehow hurt their image too much.
I don't see how anyone can support this business model. If they were an honest company, they would market their tablet on its own merits, not on how much they can cause brand confusion, or on how closely they can mimic another company's design.