Since they only release once a year, this one doesn't only have to hold its own against the competition right now, but also against whatever the others put out in 10 months.
Yeah, some people will always wait for the next iPhone. But for others, who have a more "neutral" point of view, this iPhone might look very bad in 10 months.
True, but if you look at it like Apple vs Android, the Android camp has many releases a year. So if you're a consumer and you're buying a smartphone in 10 months, your choice is between the "outdated" iPhone or one of the latest Android phones.
1) Construction (machining, materials, fitting them inside the case, industrial design). Unparalleled.
2) Screen. Top notch (high dpi, improved saturation).
3) Camera. One of the best in the business. Tons of apps for it, even photo books and indie movies videos done with it.
4) Apps ecosystem. Unparalleled in number and quality.
5) OS. Mature, not laggy, full featured, designed with far more coherence than Android and far more functionality in mind than just modernist design compared to Metro.
6) OS Upgrades. You do not even get any with most Android phones. And don't happen to the new Windows mobile os version.
7) Peripherals ecosystem: from health tracking devices, to tripods, to MIDI, unparalleled.
8) No carrier branded bullshit (apps, look etc): priceless.
A few years ago, yes the iPhone was the best in specs and had the most innovative and unique features. I don't think it holds true any more.