Not just TK. Also: AF/KL, AZ, BA, LH, and LX.
given that TK is the one that seems to gleefully undercut everyone else on the TLV market, I think TK is the big one to watch.
Personally, given the behavior of the Turkish leadership, I don't really trust them to provide adequate security/protection, and despite the great lounge @ IST and the (vastly superior to LY) onboard product, I'd rather fly El Al.