Turtling in Starcraft II will be somewhat possible for the Terran race, but more difficult for other races than in the original Starcraft. This is what Karune reported on the Battle.net forums:
Karune: “Overall, ‘turtling’ is a bit harder in StarCraft II since every race has new ways to keep them mobile. Terrans will likely have [...]

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Karune made a clarification about certain Starcraft II System Specs details that are circulating the web after a Spanish Magazine published them.
Karune: “Many fan sites are mirroring an article published by a Spanish Magazine called Micromania. To clarify, all system specifications made in that article are only speculations and are not official system specification for [...]

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