Books Online incorrectly states that CURRENT_TIMESTAMP "Returns a datetime2(7) value that contains the date and time of the computer on which the instance of SQL Server is running. The time zone offset is not included." See http://msdn.microsoft.com/en-us/library/ms186724.aspx for the error.
It appears that when the documentation was written, the "Higher-Precision System Date and Time Functions" was copied and pasted into "Lower-Precision System Date and Time Functions" without all of the necessary changes being made to the copied text.
If BOL is not incorrect, you need to reconcile how the "Return value" column does not agree with the text in the "Return data type" column of "Lower-Precision System Date and Time Functions".