I do not normally do reviews - the internet is full of them. Besides - they are usually pointless as they are usually strongly biased. I have been fortunate (or not, depending on your viewpoint) of having owned an Apple Watch since the start of May 2015. It has been three weeks now and I think I am in a position to offer some comments on the watch's usefulness.

The Ugly

1. Stand - I can make a whole dinner with it thinking I did not stand up
2. GPS navigation - turn by turn does not work, twice now it sent me on a weird 360 degree circle. Also, the fancy left tap and right tap does not work for me - it is impossible for me to distinguish between the two
3. Some iMessages never get shown. Messages A, B, C and D will be sent to me, in order, and the watch will only display say A and D. Then you reply to that but have missed B and C - possibly causing trouble depending on the content of the missing messages
4. Heart Rate monitor will have my heart rate as 80bpm when it is closer to 170bpm. It will be like that for 10 minutes before it picks up 170. Two minutes later, with me doing the exact same exercise, it will show 75bpm. Then three minutes later again 160bpm. It is not very reliable.
5. The watch will every so often lock itself while on my wrist - even with the band tight and me doing nothing more than walking. This causes the activity monitor to pause itself and after spending say an hour working out, all the data will be gone as it never warned me it turned off and never continued measuring anything. It seems to happen more often when I am carrying something heavy. And no, my arms are not tattooed.
6. Raising your wrist does not work consistently. I find that 50% of the time I either have to tap the screen or try multiple times raising my wrist, then the delay between it being raised and the actual display turning on is too long, and the duration the display stays on for is too short.
7. Siri is a hit or miss - about 40% of the times I try to use her, she either does not respond to Hey Siri, shows me a microphone button I have to press or just sits there with a pinging animation.
8. If someone sends me a picture in iMessage, half of the time the watch can show the image, the other half it wants to handoff to the iPhone to show the picture. This for the same picture.
9. The metal casing does scratch, even easier than my Tag Heuer.
10. The poor battery life is a pain. I use my watch the first thing I wake up - to know what time it is. Now that it has to charge overnight, every night, I cannot do so anymore. And no, reaching for it whilst on the charger is not practical as it displays the unlock screen. Too much effort.
11. Having to touch the watch face the whole time to interact with it causes smudges which makes reading the time hard.

The Good

1. The watch is quite pretty to look at
2. It is not heavy, in fact, it is lighter than my Tag Heuer
3. Having multiple pieces of information on the display is very useful. Instead of the usual complications, I can now see the weather, my activity workout level, next meetings etc. all on the watch face.
4. The ability to quickly switch watch faces is very useful. When I cook, I like to have access to my timer but do not care for activity. So I have a "cook" face that swaps those two complications.
5. Being able to constantly track your activity is beneficial if you want to avoid becoming normal, i.e. part of the 67% overweight population.
6. Although dorky, the heart beat IM sharing is kind of intimate
7. Being able to receive IMs on your wrist is convenient for when you do not hear your iPhone, or when it is a couple of meters from you. That said, it can also be a curse if someone spams you with messages. Feels like a little vibrator on your wrist then.
8. It is convenient to be able to add reminders and appointments hands free by asking Siri to do it - when your hands are tied up.
9. It does add benefits whilst driving - I can actually read IMs without being distracted as my wrist is at the same level as my speedometer.
10. Passbook is cool, especially coupled with geofencing. Makes paying for Starbucks easier, that is if the crooks do not steal your virtual wallet first.

Conclusion

I think it is a good concept, and if all the bugs and issues can be sorted it will be a great device. However, every day I am more and more tempted to put back on my Longines or Tag Heuer... I guess we need to give the technology time to sort itself out. And Apple should try and pour some of their billions in cash flow into QA.