Look, we're old. Not "old" old, but more like "the Olympics were so much better in Los Angeles" old. And definitely not "Beatlemania" old, but old enough to wonder if the Jonas Brothers phenomenon is anything like what we've heard about Beatlemania. We honestly don't know — before today we'd never listened to a Jonas Brothers song, we've never seen them perform, we don't even know which is which, only that the moppiest-headed one occasionally receives photos of Miley Cyrus eating her skivvies. But this week's seismic release of the new Jonas Brothers album A Little Bit Longer — and the ensuing tear-streaked, hair-gnawing tween bedlam (best evinced by the accompanying snapshot from the group's recent TRL appearance) — has us taking the Jonases' impact much more seriously. After all, today's young pop heroes are tomorrow's clinically wasted reality TV icons; on that basis alone their soaring stars deserve a closer look and deeper understanding — or at least a handy Defamer fact sheet for your water-cooler convenience. Everything you need to know is after the jump.I. KNOW YOUR JONASES