Actually, it wasn't Steam but rather Creative Assembly who had the 48-hour preload thing on their web site. Which means that CA had some reason to believe it was so; there's no profit for them in announcing something that's untrue.
Here's a semi-official satement:
Hello all,
Here is the official word regarding Empire: Total War and pre-loading:
"There is no pre-load for Empire: Total War. Due to the staggered release times worldwide, preloading is not possible and as such, Empire will begin loading at the time of release. The current release schedules for the game are:
Tuesday, March 3rd - 1800 CET / 1700 GMT / 0900 PST
* North American & Canadian Ship Date
* Steam Authentication Servers activated for North American & Canadian Retail customers.
* Steam Authentication Servers activated for all European and other Worldwide retail and digital download customers.
* Game available for sale and download for European and other Worldwide digital download customers.
Wednesday, March 4th - 1000 CET / 0900 CET / 0100 PST
* Worldwide street date.
* Game available for sale and download for North American & Canadian digital download customers.
In brief, the game will authenticate for customers at 1800 / 1700 / 0900 Tuesday and allow for European players to start playing then. North American and Canadian customers will be able to start playing at 0100 Wednesday.
That is the official word. No pre-loading.
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