Generally, I'm very happy with Aperture 3 on my laptop. Looking forward to an Aperture X revamp, of course.
Flickr integration needs tightening up. It's a bit flaky at the moment.
And if you've enabled 2-factor authentication for your Apple ID, you'll be severely out of luck - for no apparent reason - if you try to use Aperture to create a printed book. Aperture doesn't understand Apple's latest and greatest authentication scheme, and you need to turn it off to order a book. Marvellous.