Very ... but no more similar than any of the other smart phones.
A beautiful screen, a home button at the bottom & volume at the top left, which is pretty intuitive regardless.
Methinks this doesn't stem so much from patent infringement as much as Samsung being the most successful smartphone provider, after Apple, encroaching into the iphone market. Other manufacturers are well behind Samsung for hardware.
The screen visibility, in bright daylight, of the Samsung Galaxy S is much better than the iphone 4 which came out just less than 9 months AFTER the samsung Galaxy S & its' US variants. In addition, it's physically smaller, lighter & the battery life is better/comparable, has replaceable batteries, upgradeable internal memory & has a great online hacking community devoted to getting the most/best out of it.
The new Galaxy S2 promises even better screen visibility, at higher efficiency, albeit lower resolution than the iphone 4, and comes with double the ram, and dual core CPU, better GPU, slightly larger screen (a necessity due to the new technology decreasing density).
Besides the basic hardware in the Galaxy S2 is strides beyond the iphone4, and the introduction of the Android 2.3 (Honeycomb) which rivals iOS4 in response & speed, makes the Samsung Galaxy 2 an iphone4 beater.
It's become the case in the US that companies no longer compete on products, but in the court-room, and Apple is just playing the game.
It strikes me that US business practice is becoming abhorrent to the US population, not to mention the rest of the world, and the continued practice suggests decadence of US business, as they attempt to stifle competitors innovation. This business practice can only stifle innovation, and of course, prevent improved products entering the US market. At the same time, the rest of the world doesn't respect the US courts, and will continue to purchase the superior products.
Apple will soon be the new GM