CREATE TABLE table_26998135_2 (replaced_by VARCHAR, date_of_vacancy VARCHAR)

Who is the replaced by when the date of vacancy is 27 december 2010?
SELECT replaced_by FROM table_26998135_2 WHERE date_of_vacancy = "27 December 2010"
SELECT "replaced_by" FROM "table_26998135_2" WHERE "27 December 2010" = "date_of_vacancy"