Some of my current favorites:

iReal Book : http://irealbook.net/page2/page2.html

S1 Midi Trigger : http://web.me.com/miu.aco/miuaco-software/S1MidiTrigger.html

iElectribe : http://www.korg.com/Product.aspx?pd=577

iMS20 : http://www.korg.com/Product.aspx?pd=585

Music Studio : http://www.xewton.com/musicstudio/overview/?dev=2

AmpKit+ : http://www.agilepartners.com/apps/ampkit/

Songwriter's Pad : http://www.dantemoore.com/songwriters-app-ipad-iphone/



Now if some of those apps don't get you interested in music on an iPad, I don't know what to tell you. lol


Personally, I am finding that my iPad is becoming a useful (and portable) part of my of my musical arsenal. Of course, in reference to the article's point, my knowing a little something about music is a key part of that usefulness.