Where I was the US, 7pm - 9pm was prime entertainment time, and the news would start at 9pm or 10pm depending on the channel (which I think was partially so TV would become boring to kids right around when they should go to bed). Don't remember how long it ran, though my guess would be an hour before the late-night shows would begin.
In Chicago, there was only a single news broadcast that _wasn't_ at 10pm and that was Channel 9. It was part of their marketing to have the news at 9 (channel 9, news at 9). In the mid-late 80's when Fox came online, they copied the 9 o'clock news.
As I recall in the US, there was typically a post-primetime local news broadcast. The network news was pre-primetime (and it may have been accompanied with a local news slot beforehand).
As far as I'm aware the 20:15 thing here in germany is because nobody want's to compete with the "Tagesschau". In other countrys where I lived all the channels would start their movies whenever they want(7pm, 9pm or such strange times), as a german I found that pretty irritating, who could live like that? It's pure anarchy. :)
Back in my day and in Germany, "news" was from 20:00 to 20:15 with the last 5 or so minutes of that were dedicated to the Bundesliga :)