Decided to go ahead and install NXE. I also found NGII for cheap today, so I bought it and installed it.
It is fucking awesome, as the thread title says. Way easier to navigate, fast as hell. Only complaint is that it's too wordy. It's not just a "Games" or "My Xbox" tab, it's "Games - blah blah download new and exciting blah blah blah today!" or "My Xbox - Blah blah customize blah blah blah your xbox 360 etc. etc." This is just an aesthetic thing, but really quite tacky to have to look at descriptions every single time you are in the dash...as if you're going to forget what the "Music" tab does or something.
NGII installed in a few minutes. Loading times are definitely better. The game seems to run better after the latest update...but perhaps it's streaming faster off the HDD too. Also, forget about Jasper/Valhalla/Xbox Ultimate Super Edition, the air blowing out of the 360 after about 2 hours of play was barely warm. This thing is hardly putting out heat and I'm guessing RROD will get cut down even more (is it still a problem with Falcon's anyway?)
Another cool feature I didn't pick up on in coverage is that you can hop from game to game without having to go back to the dash, which is nice.
Only major complaint is that 1440x900 seems gimped. My monitor is 1440x900 native and I'm still getting black bars. I don't know if this has anything to do with using the VGA adapter, but it's pretty annoying since 1280x720 is stretched a little. Maybe the real release of NXE won't have this problem?