Going ahead with the switch to tabs. This is a major coding standards change! If any unusual parser bugs show up, check this changeset. Converted all .php, .js, .tpl, .css, and .json files and did basic testing.
ALTER TABLE {{TABLE_PREFIX}}users_extra ADD COLUMN date_format varchar(32) NOT NULL DEFAULT 'F d, Y';
ALTER TABLE {{TABLE_PREFIX}}users_extra ADD COLUMN time_format varchar(32) NOT NULL DEFAULT 'G:i';
ALTER TABLE {{TABLE_PREFIX}}lockout ADD COLUMN username varchar(255) NOT NULL DEFAULT '';
ALTER TABLE {{TABLE_PREFIX}}logs ADD COLUMN author_uid int NOT NULL DEFAULT 1;
UPDATE {{TABLE_PREFIX}}logs SET author_uid = 1;