It's my understanding that HTC is simply putting the phone in to a deep hibernation mode when turning the phone off and "Fast boot" is enabled. Are there any disadvantages to this? Extra power draw? Memory footprint? Since we are sometimes told to power cycle our phones when offending apps or other various problems are occurring, will this not be as effective when "fast boot" is enabled? It appears that the "Restart" option seems to be doing a full power down cycle so maybe this is a moot point (I could be wrong here, though).