The City of Splendors is still one of the greatest cities on the face of Faerun, even if its power has somewhat diminished after the Spellplague. That said, the city was otherwise unharmed by that catastrophe, and it has been steadily growing in power and influence in the last 100 years.
While Neverwinter was always more cosmopolitan, and Baldur’s Gate is now the larger city, neither can hold a candle to the sheer entrepreneurial spirit and breadth of history and experiences of Waterdeep. The city is fairly bursting with churches, guilds, noble houses, and societies beneficent and malevolent, all vying for money, power, and influence.
Everyone on the Sword Coast has heard of the shining Spires of Morning, gleaming with first light. Or the Plinth, with its worshipers of strange, forgotten gods. Or Castle Waterdeep, its flags proudly dancing in the ocean breeze. It is a storied, almost magical place.
Currently, Waterdeep is run by perhaps two dozen masked lords, led by the open lord, Dagult Neverember.