The Allen Economic Development Corporation has a nice report on the the Data Center proposal for the Stacy Road location that Cisco is most likely building on. Good power, fiber connectivity and financial incentives = data center site selection. The local utility for this area, Oncor announced last week that the "World's largest concentration of smart grid voltage compensation equipment placed in service by Oncor".
Allen Texas is about 25 miles north of downtown Dallas. There is also a sizable Cingular data center just a little bit south of the Cisco site in Allen.
Check out the press release here
Here is a map of the Allen, Texas data center site
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