Too funny these Ap vs Lr discussions are. Both programs do the same thing and are in direct competition with each other. Each gets better than the other with each release and update, adding new features etc to try and better the other and so forth and so forth....
Download BOTH and play with BOTH and decide from there.....I've used BOTH and prefer Aperture PLUS I don't think the extra $100 is worth it for Lr but BOTH programs are great.
To answer your question, if you want more power for editing and enjoy post processing your images then definitely get either Ap or Lr over iPhoto. If you just use the auto enhance features of editing programs then you'll be fine with iPhoto.......
Download BOTH and play with BOTH and decide from there.....I've used BOTH and prefer Aperture PLUS I don't think the extra $100 is worth it for Lr but BOTH programs are great.
To answer your question, if you want more power for editing and enjoy post processing your images then definitely get either Ap or Lr over iPhoto. If you just use the auto enhance features of editing programs then you'll be fine with iPhoto.......