I’ve had the same problem with Cycles. It really depends on your cpu power (or whatever it is) and I don’t see Cycles speeding up any time soon. I was making a floor plan once, and needed a single frame, so I left it for about half an hour and then came back, and it was lovely! I think if you do want a nice animation, your only option is to wait ages for each frame, that’s the only way around it, but it does bring out better renders (my lovely floor plan : http://www.pasteall.org/pic/30279 )
I heard somewhere about being able to use gpu (your graphics card) instead of cpu (your computer power or something like that) which is supposedly quicker, why don’t you try that. I don’t think it works on Mac, but apparently, this is how you do it (http://www.pasteall.org/pic/30280), why not give that a try!