After about 2 weeks of being live and only available in Quick Play and other non-competitive modes, the reworked Symmetra is now live and available to play in Competitive ranked Overwatch.
Her newest rework changes all of her abilities, making her primary fire a straight beam, her secondary fire charges and moves faster and now explodes on impact, she can launch turrets at range to attach to the first physical object they touch, her teleporter is no longer an ultimate and can teleport objects like D'Va's mech and Torbjorn's turrent, and her new ultimate creates a wall of infinite height and length that has 5000 HP but has a short duration.
You can read-up on Symmetra's new toolkit on the official Overwatch website here: http://playoverwatch.com/en-us/heroes/symmetra/