Your typical smartwatch currently are generally all the same, they tell you the time and your primary device's*1 notifications. Trying to do anything else heavy on it is ludicrous, especially with their battery life.
Not many people realize that all batteries in current smartwatches are framed in a squarish size which is evident in my smartwatch the moto 360's*2 320mAh capacity. I normally get a 12 hour at minimum out of my use case which you can see is more than fair considering the particular chipset. Currently there are at least one manufacture*3 who is creating hexagonal batteries which should help bring up the amperage it can hold.
As a side note, there are field tests already happened that modifies current WiFi technology to provide power to a compatible device*4. If you wanted to monetize on that I would recommend to use the normal part of WiFi and add some sort of data transfer protocol which would provide with how much energy the device pulled then set up a city wide WiFi.
That being said; when battery life is no longer the issue the only thing that would be stopping it from checking your Facebook would be processing power*5 and screen size.
I envision later to fix the screen size issue by using holographics-like technology or maybe AR contact lenses, which BTW is pretty much what Google Glass was probably a test for considering it came before Android Wear.
Android Wear currently as it stand is pretty nice but should be considred as all the way back on Android 1.0. With a good basic feature set if you're a fan of the OS I'm sure you would be glad to hear that yes, it is finally finished.
A few things I can do with my smart watch is notify, as in vibrate, when 10 minutes before work, play music stored locally on the smartwatch via Bluetooth; control music from Google Play Music app*6 playing from my smart phone's volume as in play and pause, skip and previous song, thumbs up or down, and also browse to play a new queue (which crashes Android Wear app*7 consistently as of now); figure out how much exercise I did that day, and ask it a general question about anything since it is a Google device, which I say like that since Chromebooks*8 have this ability as well.
A few things I can't do with my smartwatch is do anything internet related (Android Wear has native apps just not many) without my smart phone being on, bad notification support by relying on notification from primary device (example being requesting an Uber and no where does it say how long until it gets here), bad command support (example being with again Uber not supporting the call a car command), and of course survive a full day*2.
In closing, I would say smartwatches are going to be some day something I would suggest to everyone just not now.
Comments and References:
*1: I say primary device because it doesn't have to be a smart phone
*5: My particular smart watch can be a bit slow, also I may or may not be writing a review on it as you're reading this.
*6: I love gpm!
*7: I kinda despise this app but recognize it's a necessary evil
*8: Since you read this far you should also know that I'm probably gonna do a Chromebook review too later