Only had a few hours to test drive it, i have it on my rooted Samsung Galaxy S3, and i must say i am loving this. i've never kept the stock launcher before, but the Google Experience launcher fits. it works well, and there are many things they've done to improve the once half-put-together feel of Android (remember, i came from the iPhone): 1. Notification Bar I remember the first time i had used Ice Cream Sandwich and up. i HATED the 'digital/electric blue' status indicators. for some reason, bright, digital/electric blue (most electronics use this color for their power LEDs or digital clock displays) hurts my eyes. then, i preferred the greens of Gingerbread and often downgraded an ICS device back as a result. So the change to neutral white is a welcome and more pleasing-to-my-eyes result. the transparent look is also nice, and doesn't break up the screen or appear to take up space in apps. it fits almost as an overlay on top of an app without shrinking the size down. Grouping of the notification icons is also nice, instead of redundant and multiple Play Store icons for each individually installed app update taking up all that space and making my OCD go nuts, they now appear to group most notifications with more than one alert under one icon, expandable in the notification shade. this helps clean it up a bit, although i'd prefer it if they'd just remove the icons and introduce app badges and make the notifications only show when you pull down the shade. it still doesn't take long before the otherwise clean notification bar is filled with icons. all that should be there are things like signal status, wifi, etc. 2. Google Now is automatic I hated having to launch Google Now manually and then saying 'OK Google' to voice control my device. it took an extra step that made no sense. so now i'm extremely happy they made it automatic. no matter what, saying 'OK Google' enables it. you don't have to be in Now or in the search app. as a fan of Star Trek and its voice-controlled computer systems, i'm very happy they made it automatic. Google Now also is on a left-swipe from the center, making it a bit better than holding down Home (especially if you got Home programmed to do something else in a rooted device) 3. ART!!! No, not paintings. the new VM. Dalvik always seemed to be an achillies heel to the Android platform, even causing a bit of lag in Jelly Bean, and making it feel half-put-together if you are used to the smoothness of the iPhone. flagships minimize it a lot, but it's still there. and yes, you can still run out of RAM if you got as many apps installed as i do, and it's not very cool to have your phone randomly reboot itself if you got a lot of things going on (random reboots are kernel panics, often caused by OOM or Out of Memory problems--they're designed to fix the problem without the phone freezing and requiring a battery pull--yes, i'm looking at you, BlackBerry). ART is Android's way of bringing the iOS smoothness to Android. it even goes one level farther and makes apps almost instantaneously start up. no more black screen and 'Facebook is not responding, do you want to close it?' popping up if it takes too long. took them four years but thank GOODNESS!!! I'll probably see more, but right now i'm happy, as the only newer ROM i had before was a beta of Carbon, running in Android 4.2, and it was extremely buggy and half the things didn't work well. i was considering going back to iPhone but glad this came out.