Download Speed Limited?

What%26#39;s the determining factor when downloading demos from Marketplace? My PC can download a 70mb file in less than 45 seconds at 733 kps (sometimes higher than 850 kps) and it%26#39;s using the same exact internet connection as my 360. Does Microsoft limit your download speed from their servers?Download Speed Limited?
I download stuff off the marketplace a lot faster than 850 kbps. 

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