“Nina Sky is limitless: hip-hop, reggae, rhythm and blues, rock, alternative, jazz, funk and soul.” At least that’s what this new duo, consisting of 18-year-old identical twins Nicole and Natalie Albino, says in the spoken intro of this disc. And the Queens sister act indeed delivers a decidedly eclectic effort. On just the hit first single “Move Ya Body,” they incorporate booty-bumping dance-hall (including guest vocals by Jabba), an insinuating Middle Eastern synth riff and bits of Lisa Lisa and Cult Jam’s 1985 freestyle classic “Can You Feel the Beat.” The result is one of the summer’s big club anthems. When they keep the party pumping on cuts like “Turnin’ Me On,” a sexy come-on in the vein of Beyoncé’s “Baby Boy,” Nina Sky is airy fun. But the disc is dragged down by slow jams that are just, well, slow. Unlike another R&B duo, Floetry, Nicole and Natalie don’t have the voices or the songwriting Nina Sky makes a less-than-lofty debut. skills (they cowrote all 14 tracks) to attain the kind of musical heights they reach for on ballads like the Latin- tinged “Temperature’s Rising.” This Sky does in fact have a limit after all.