Muggles turned out en masse for Friday's official grand opening of The Wizarding World of Harry Potter. Tucked inside Universal Orlando's Islands of Adventure theme park, the line to enter the richly themed area circled through the entire park.

I was there, quickly abandoning what at one point reportedly became a 10-hour wait. I was able to enjoy the attraction a day earlier without the madness -- one of the perks of staying at one of the three on-site resorts.

The opening's success bodes well for a healthy summer at the park -- jointly owned by Blackstone Group (NYSE: BX) and NBC Universal majority parent General Electric (NYSE: GE). Beyond the Potter-powered boost in overall park attendance, the lines were long for folks willing to fork over nearly $30 for wizard wands. Fans were also chugging down pumpkin juice, butterbeer in keepsake mugs, and chocolate frogs at healthy markups.

Author J.K. Rowling's already rich, so the crowded stores and concessions will only pad her fortunes. The Time Warner (NYSE: TWX) film series is gradually working its way to the saga's climactic conclusion, and a themed attraction won't necessarily move more movie tickets or DVDs.

The real winners here will be Florida and the theme-park industry. Universal Orlando will be a tourist magnet this year, which is great news for Disney (NYSE: DIS) a few miles away. Families heading down to the state for a week will indubitably find themselves spending time at neighboring parks.

However, Blackstone is the company to watch here. It acquired the nearby Sea World and Busch Gardens attractions last year. Its Merlin Entertainment unit is also set to open Legoland Florida just an hour away by the end of next year.

Florida can certainly use the tourists, as BP's oil spill has left the state's Gulf coast beach resorts smarting.

This was already shaping up to be the most interesting summer in years for the amusement park industry. Cedar Fair (NYSE: FUN) will have to prove itself worthy after rebuffing an unsolicited buyout bid earlier this year. Six Flags (NYSE: SIX) is back in the spotlight. It began trading this morning after completing its bankruptcy reorganization.

The huge Potter opening proves that patrons will reward a park operator that spends to expand and enhance its gated attraction. After laying low during the recession, the amusement park industry is springing to life in this crucial summer season.

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