iOS 9 is set to release today, but watchOS 2.0 looks like it'll be a no show. A new report says Apple is pushing watchOS 2.0 back a couple days to work out a major bug—presumably one that's big enough to for a release delay.
watchOS 2.0 release delayed for bug fixes
An Apple spokesperson told Tech Crunch,
We have discovered a bug in development of watchOS 2 that is taking a bit longer to fix than we expected. We will not release watchOS 2 today but will shortly.
Apple isn't saying exactly what needs to be fixed, but it's a safe bet the problem is large enough to be a show stopper.
Apple had originally planned on releasing watchOS 2.0 along side iOS 9 on Wednesday. Both will be available as free updates, but for now only iOS 9 will make an official appearance today.