Ease of use
Ecosystem (apps, drivers, etc.)
....it's not prime-time yet. Running it under VMWare Fusion on a MacPro was real slow and pretty much non-useful at this point. You can play with this and see where they are going with it, but it's not there. Not all of my gmail boxes showed up and trying to move around was painfully slow. It sure didn't like my Wacom Bamboo as a pointer/mouse (though to be fair VMWare doesn't like it much either if more than one VM is up and running at the time, so it may not be Chrome). Maybe someday I'll try it again, but for now we'll just wait and see....