If you have a missed text, a missed call and an email and your multi-colored LED is blinking, can you touch the LED and see previews of the text and the email and see who called so you can decide which, if any, of those you want to respond to right away and which ones can wait?
So right now, my phone is slowly blinking the time, the temperature, and a little image of a letter. It doesn't tell me how many unread emails I might have, or who they are from, or even which email account they came in through. And most of the time the screen is blank -- if I even want to know if I have new emails, I either have to wait for it to blink on, or turn on the screen.
My prior phone showed an LED that told me with a light that stayed on whether I had a new email, and the color indicated which acocunt it came in on -- which is actually a lot of information given my email use. True, it didn't give me the time or the temp, but I don't really use either of those.
With both phones (Moto X and Photon) touching the screen gives me info about the nature of the emails, or at least, of othe most recent email. Maybe I touched the screen and pulled down the shade on the photon. It certainly wasn't a lot of effort.
With the LED notification, you have to light up the entire screen in order to get the details of the notification (type of notification, message sender, preview of contents, etc.). Even simply dismissing a notification requires you to turn on the entire screen. Turning on the screen over and over again wastes battery life. You can use an outside app light Light Flow in order to get better notifications, but you still won't get as much as you will with Active Display. Active Display will only light up enough of the screen to give you those details, which is one of the reasons the Moto X gets such good battery life.
The battery life is certainly an improvement, but I don't think it is much of an improvement over when the old phone was new. Mostly, I think I am benefiting from a newer battery. I still have to plug in the phone at work if I plan to go out in the evening.
It's a fine phone. and I get that active notifications are cooler than a colored LED. For my use, they aren't much of a functional improvement. I am move excited about improvements in handling contacts that have info both from Google and from Facebook (something I had on the Pre, and missed on the Photon.)