Create Digital Music’s own Peter Kirn has created an up-to-date (February 3, 2011) article on Practical iPad music making. One focus is on getting MIDI in-out of the iPad to increase its usefullness as a controller.

Because of the hardware i/o limitations (USB power reduced to 20ma by iOS4.2, delicate docking port) and Apple’s crotchety, paranoid, closed-shop approach to software innovation, the iPad may remain a fancy controller rather than becoming the core of any MIDI-based performance.

In any event Peter mentions several hardware and software products (including video) that may be useful (or may be included as advertising). He includes the following video.