Found this useful article from Social Media Strategy and Marketing consultant Howard Greenstein. It helps to de-mystify these too FB functions. One thing he doesn't mention is how Pages also offer "Insights" about visitors to the page gleaned from what FB already knows about these members, like age and gender. Similar to Google Analytics.
“Should I create a group or launch a Page?” It’s the eternal question that gets asked as often as, “What is Twitter?” at introductory social media training classes. Ever since Facebook launched their Pages product as part of their larger advertising strategy (along with the ill-fated Beacon) in November 2007, there has been confusion over which to use. Because
Groups and Pages have an overlapping feature set, even senior social media marketing consultants are sometimes stumped as to what to tell their clients. And Facebook continues to make changes to how Pages function, complicating the matter even further.
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