iOS 8.0.2 will be arriving in the next few days and it'll fix the iOS 8.0.1 bugs bugs that caused loss of Touch ID and cellular service on the iPhone 6 and iPhone 6 Plus. That's according to a knowledge base article just now posted on Apple.com:
We are also preparing iOS 8.0.2 with a fix for the issue, and will release it as soon as it's ready in the next few days.Apple also details steps that can be taken right now for anyone affected by a bad iOS 8.0.1 install. (Reassuringly for us, they appear virtually identical to the steps we posted earlier today.)
The Health app won't work following reversion to iOS 8.0.0, but that too will be fixed by iOS 8.0.2 in the coming days.
If your iPhone 6 or iPhone 6 Plus were affected by iOS 8.0.1, let me know if you managed to get them back up and running, and how they're working for you now.