As to the frequency of the power off issue, keep in mind that people generally don't post about a problem unless they are experiencing it. And if they are having the problem, then there is a very good chance that they would post about it. So an unscientific way of calculating the frequency is to 1) count the number of people that posted to the power-off thread, and 2) count the number of people that have posted to any other issue that is likely to affect everyone. If these two counts are taken from different time periods, then adjust the numbers to reflect the number of users on this forum at the respective times. Also factor in the impact of the two issues that you are comparing (a higher impact will get more people posting about it).

For the record, I haven't experienced any power-related difficulties on my N800.