I'm a Mac user, and I've been using Logic for the past 5 years. It's the most 'logical' (pun intended) interface for recording organic audio. I actually record to an all-in-one and then export the separate instrumental tracks to Logic, and then record vocals directly to Logic. I use an old-school all-in-one Yamaha machine because it can handle 8 simultaneous inputs better than my MacBook Pro ever will.

Also, if you'd like to make rap beats and whatnot, FL Studio 10 is amazing and extremely user friendly (only for windows though, so you'd need bootcamp on a mac)

I do like Reason for beats as well, but the interface can be cumbersome to figure out at first.

Logic has really, really nice samples for midi as well, but it's extremely hard to work with unless you're recording to midi using a midi-compatible keyboard.