With regards to the suggestions of integrating NTP into the bitcoin client, I think it is a bad idea. The bitcoin client is simply not an appropriate place to put timekeeping software.
If I were emperor, I would make the client turn red if it thinks the local clock is off by more than 5 seconds from what the peers report, and refuse to run if off by more than 30 seconds.
Some of these systems need a color worse than red, but I think 5 seconds is too tight. 1 minute would throw a blanket of most of them, and a popup message to the rest pointing them to instruction on how to fix their clock would suffice for the rest.
In light of a global system capable of keeping every clock on or near the planet (maybe even in the entire solar system) synchronized to within a dozen milliseconds or so, I would say that a 5 second skew is evidence of a serious error.
It's interesting to note three are 1 hour, one is 2 hours, and three are ~24 hours off. I wonder if that is deliberate (run your computer in a different timezone so you now when to skype your grandkids), or a curious mistake.
Both. Computers are capable of displaying the time as an arbitrary offset from the system time. If the system time is wrong, that is a mistake, even if the reason it is wrong is because someone did it intentionally.