I don't know if it's a sign of my decreasing interest in "the latest thing" or Apple slipping a bit, but I haven't felt any particular urge to buy any of their most recent new products (MacBook, Apple Watch,

TV4, and now iPad pro).
I can feel for you here, but my interest is not decreasing in "the latest thing" but rather Apple itself. I have gotten more excited over the new Nexus phones, Surface Book, and heck, even the Blackberry Priv than I have with Apple's new string of products. The MB was a big joke. All we wanted was a retina screen in an MBA, but they gave us this gimped notebook with 1/10 the power of an MBA and 2 ports.
Apple Watch is okay, but not something I'd say competes on the level of the iPhone, iPad, iPod, or Mac, and it really is a solution in search of a problem. Can't say that I'd recommend it to a friend, at least in its current state.
Apple TV 4 was supposed to be a major revolution, but all they gave us was a taller ATV 3 that now has "the future of television" (apps) that have been around for years on other streaming boxes. With the amount of hype they had around this event, I thought they were going to blow every other competitor out of the water. Didn't happen.
And last but not least, the iPad Pro. The problem with this is that it's just a larger iPad. It costs a crap ton of money, has a smartphone OS running with a couple tweaks (Split screen), has a bunch of accessories to give you the full experience that cost another $200+ on top of the large price, and it can't run any true "pro" apps. Does anyone at Apple take this "Pro" name seriously? It doesn't do nearly anything worthy of its "Pro" name. Cook says it will replace many people's computers, but let's be real, at its current state, it's not doing anything "Pro" that would make people rush to get rid of their computers.