I hope I don't upset anyone...
I like people describing "why" and "how" and not "what" they did. I enjoy seeing the way peoples minds work and how that affects their game styles.
Everybody Eulagises (sp) about Sir Pleb. But his reports are exactly the sort of thing I am talking about - though they do have a tendency to be a little overlength (dare I say). My posts are more than a little overlength. 50 lines of rubbish punctuated by the odd phrase of utter rubbish.
Turnlogs are a complete turn off to me. In SG's they are necessary and interesting as you are involved in the SAME game yourself, but in terms of a GOTM spoiler.. well I don't even look at them in truth.
I like the logs that include minimaps at various stages, or for culture wins - charts showing the rate of culture increase. Anything that shows the RATE of progression.
I like the logs where people moan about their bad luck. They just crack me up.
I like Drazeks reports. "Yeah yeah once I upgraded my units I was able to reach domination in 270BC, about 20 turns more than optimal. Total playing time 4.5 seconds"
I think he just cuts and pastes this every month. Completely uninformative of course, but very amusing.
...And finally, the Sagas. I'm sorry but I don't like them, and I hope that most of the authors don't give up their day jobs... I played an SG once where it was obligatory to write your reports in this manner. Mine were excruciatingly bad.

But I don't have time to read Saga's properly, I can't follow what happened in the game, and before I am half way down them my teeth are on edge. It's a bit like watching a video of yourself singing karaoke - just too painful.
Most of all, I can't read long posts. Half the size of this one is about right for me.