GEAR4 has unveiled several new cases for the iPod nano (with video), in both leather and “urban” models. The LeatherJacket N3 features a black leather outer with magnetic snap closure, a fold-out stand design, and a clear screen protector. It will sell for £15, or $30. The LeatherJacket Quartz features a patent leather outer with magnetic snap closure and a clear screen protector; it will also sell for £15, or around $30. The LeatherWallet…