I downloaded 4.0 this morning. While a lot of it looks like GB, there is a lot more flexibility. I love the idea of folders, to save on the desktop space. At first use, the phone seemed to lag and bit and a bit of unresponsiveness. Then I had to remove the battery and replace it and it practically didn't read anything on my SD card. Eventually, the information seemed to have loaded. Also, downloading some of the apps, seemed to have gotten stuck in the process.
Over the course of the day, it seems the phone has gotten faster and more responsive, without any kind of reset. I was able to reload some apps and I was able to get the connection I was used to. Now over the past few weeks, I've used the GO launcher, haven't gotten one white HTC screen with Go Launcher. I used SENSE and at first it seemed to work fine. Later I got the white HTC reboot screen, so I've gone back to Go Launcher. It's been super smooth since!!
I'm anxious to see what 4.0 improvement will come with the apps. I do love the 4.0 versions of G+, Google Talk and Gmail. Only exception in Google Talk, seems to have taken away the ability to sort ALL your online contacts, just most used contacts.
Overall, I'm pretty impressed with the upgrade (so long as I use GO LAUNCHER). Seems sense still has some issues.