It's already on a couple other blog sites already, where you can check out the various law enforcement guidelines.
For example, how "Player Mail is not maintained for more than 180 days."
The document doesn't really cover Player Chat very well though. It says they can do realtime monitoring of chat, and they describe Player Chat Logs, but they don't say anything about retention of older chat logs.. so, they only retain old Mailbox messages?
There was also another contradiction. In one paragraph, Blizzard wrote "Warcraft alone has more than 9 million active users worldwide spread across several hundred servers", but later they wrote "Because Blizzard has over eleven million active users, Blizzard does not have the ability to retain all types of information indefinitely." In December 2008, they announced 11.5 million subscribers and then in Feb 2010 Morhaime announced that there had been no growth since 2008.
Maybe they dipped quite a larger subscription number than everyone had estimated? (e.g. 11.5 to 9 million)
This was the really interesting part though:
Blizzard currently maintains more than 500 WoW servers with well over 100 dedicated to the North American region.. Each server can host more than 3500 players at the same time.This is the first time I've ever seen a source directly from Blizzard confirming the maximum number of concurrent players per realm (i.e. "players at the same time"). It was always estimated that each WOW Realm could support about 5000-6000 concurrent player logins.
Although WarcraftRealms isn't a very good source for total player counts (because there's a lot of overlap of players), it is a very good source for daily player activity.
If you look at the Average Daily Activity Chart here, it shows total number of players logged in during each hourly interval. Remember though, that the same players might be logged in for 8 hours straight. And, if you look at the graph below the chart, they all max out at around 3500 concurrently per realm. :)
If you assume that an average player spends 3 hours per day playing WOW, that's about 6950 unique players per realm (on average) that play throughout the day. Blizzard has less than 900 realms worldwide, which makes it about 6.3 million players.
I wouldn't be surprised if this 2009 policy is the exact same one still used today. Documents like these are very rarely updated, and it doesn't look like they spent a lot of time preparing it. Still, it's pretty interesting..