Exactly Command+S has started to work again, so you easily save screenshots. Just as you can develop iPad apps as well, without owning an iPad. All you really need is a mac, although having a device really helps testing.
Yeh, you guys are right. As a practical matter, I feel like you need either an iPhone 5 or a retina display on your mac. When I use the iPhone (Retina 4-inch) simulator on my (non-retina) MBP, I can't see the whole thing on the screen.