“Little Worlds” is one of the coolest and most inventive jazz releases of the year. The first studio album for Bela Fleck and his Flecktone bandmates since “Outbound” in 2000, “Little Worlds” eclipses everything this group has released previously. The album is an ambitious three-CD release that must be viewed as a watershed moment in Fleck’s career. It is one thing to appreciate the banjo as a weird instrument—Fleck’s starting point—and quite another to mastermind a jazz album as thoroughly cutting edge as this one. Fleck’s core compatriots (Victor Wooten, Future Man and Jeff Coffin) deliver nothing less than stellar work. A host of guest players—which includes Derek Trucks, Bobby McFerrin, Divinity and the Chieftains—performs with equal inspiration and gusto. With “Little Worlds,” Fleck’s bluegrass/jazz fusion (blu-bop) is given its most definitive and gripping articulation yet.—PVV