How are winners determined in general?

[Byron]

Just wondering how the winners are determined for give aways. I've entered about a dozen over the past 18 months and haven't won any. This morning a new one became available and I entered the contest at 6 AM EDT. There were already 100 people vying for 10 copies.

The time stamp on the notification email was 4:08 AM. Are the emails timed for 8 AM Greenwich time? If so, are winners determined by how early they submit a request? That would give European members a significant advantage in winning if it were the case.

[L.C.]

I always thought they were picked randomly. I don't think it matters what time you enter otherwise why would anyone enter on the last day?