Just take the plunge man. You seem like you enjoyed your 360. The One is a natural successor and you might even enjoy the use of Kinect.
The 360 was my go to system in almost every way - 99% of my online time, 90% of all my digital downloads, a good 85% of all my games purchased last-gen (and virtually every multiplatform game on the platform until I got a gaming level PC late in the gen).
But it's not my time yet. II feel Microsoft has to learn a lesson for what they attempted much like Sony had to in 2006 (which is why I didn't get a PS3 til Uncharted 2 was basically out) and I don't think lots of people buying in early on will teach them much, so I'm doing my part to stay out of it. Additionally, there are still many things that I don't like, such as Kinect, and I don't really want to spend the $100 extra for that technology I won't ever touch. So even if I wasn't annoyed at MS for what they attempted, I probably would have to wait for the first price drop.
I think I'll get it when it hits $299.99. Forza will definitely be one of the first games I get though. They also get it - 60fps first, then see what else you can get it there later. Sure in sheer technical terms, it's not doing as much visual wizardly as their competitors flagship launch racer, but I'd give that all up to have it in 60fps, so I feel they have their priorities straight. Also almost every Forza game I have played was great, and the last Forza game was better than Gran Turismo 5 in many ways, so Turn 10 keeps improving. I expect Forza 5 to be a bit of a step back from the last Forza game though since, like all launch games, it'll be rushing to make that launch deadline. But that's cool... a taste of things to come