i've seen mixed reviews so i thought i'd throw in my 2 cents.
battery: i was ready to return this thing the second day (and save the $35 restock fee)! the first day i was in a strong signal area and was running the 4g radio and i got about 1.5-2 hours of actual use and about 8 hours of standby. i wasn't thrilled, but could live with it and figured i would end up getting the extended battery (which, at the time, they were sold out of). however, on day two i went to a friends with poor coverage. it was literally dead from a full charge in less than 5 hours. i was going to return it but figured i would see what happened when i turn off the 4g radio. the next day i got 3+ hours of actual use and over 15 hours of standby time. i was thrilled with that (stock battery, no task killing nonsense, pull emails automatically every 15 minutes, and a very bright screen setting). so now i'll just keep it on 3g and activate 4g when i want to stream or download something large. i'm using the "LTE on/off" app (thanks pjnc).
new sense ui: great! my favorite android UI is now even better!!!
size: a BEAST! i got the incredible last summer instead of waiting on the moto X because i didn't think i'd like the large size. i was wrong. i'm blown away by the tiny difference in screen size. it is so much easier to touch the correct icon, link, etc when i'm browsing. also easier to type. there are very minor differences that i'm noticing and i really like them so far (email messages scroll in from the side when you advance to the next one. silly little things like that.)
speed: maybe it's just because my Inc was nearly a year old, but the new snapdragon processor appears to dust my Inc's processor. i have my email set to download the full message (text and images) in the body when i open it and it IMMEDIATELY appears with the full blown email (just like on my pc). blazing fast. i have loaded this up with all of the same apps and widgets i had on my inc so i believe it's a fair comparison.
also lovin the silly little kickstand.
overall, i think htc has done another great job. i still think these need to come with larger batteries (there just HAS TO be a way to get at least an 1800 mah in these, stock). i'm also still a bit disappointed that skype wasn't integrated. and finally, some apps that worked on my inc, do not work (or at least as well or smooth) on this, but i suspect most of the developers are on it.
If I got the Motorola phones, I would have Lauchner Pro loaded so fast it wouldn't be funny. Since i am running the Aria with full stock Sense, I am realizing HOW much I enjoyed using Sense. 