This New York Times article from November addresses the thinking behind the limited run:
http://www.nytimes.com/2011/11/16/theater/disney-starts-small-for-newsies-the-musical.html?_r=1 With “Newsies,” Disney is starting small. The production will cost about $5 million, and is scheduled to run at the Nederlander Theater only from March 15 to June 10. If the musical is a hit, of course, the run could become open-ended.
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Thomas Schumacher, president of Disney Theatrical, said in an interview that the three-month run for “Newsies” did not represent a lack of faith in the musical, but rather a vote of confidence. “Newsies” was developed to be licensed only for regional, professional and amateur productions — not unlike such other Disney stage shows as “Aladdin” and “High School Musical,” which have never played Broadway.
A New York run for “Newsies” will increase the value of the property in future licensing deals, more than if the show had simply been licensed after the production at Paper Mill, Mr. Schumacher said. If the Broadway run ends up lasting three months and does not recoup, he added, “I’ll be left in a slight deficit position, but I’ll make up for that in licensing.”