Best photo managing/editing software for Mac

Hi there,

Until now I am managing and editing my photos with iPhoto'11, but my collection is growing fast and already beyond 40,000 pictures. So iPhoto is getting a little slow (no 64bit) and complicated to sort photos (I just like to skip past my vacation pictures and flag those I like and then put them in an album. Though after doing this there is no easy way to delete the not flaged pictures easily in one click, right?) I would also like to have some software which gives me a few more editing options.

So far I was thinking about either Aperture or Lightroom. Which one do you think is the best choice or do you have any other ideas? I would also like to keep moving my photos as little pain as possible. Do you by any chance know an app which can pick out blurry and out of focus images so I can delete them right away? Oh and most important of all it should be easy to use ( at least the basic functions) :)

Thanks for any ideas!