Glasses, Watches, or Both?

Everyone knows Google is developing 'glass,' and it also seems likely, based on rumors, both Apple and Google are developing watches. Let's discuss which idea we think will dominate the future, or if both will co-exist. If both are eventually adopted by the main stream consumer, will people adopt one or the other, or wear both?

Personally, I imagine a future in which a person can go buy a phone from Google play, and will be asked if they would rather have a Google Watch of Google Glass bundled to interface with their new phone. It seems these devices will be complements to smartphones, and not devices intended to be used on their own.