Fantastic. Aperture's eventual collapse has me worried as I'm packing more and more photos in. Tried Lightroom every year but hate it's rigid "modes".
For a photography DAM app, these are the killer features (excluding fast, stable, non-crap UI):
Referenced files: let me choose where to store the RAW files (so many apps can use it), and the DAM generates previews for fast display that it stores within itself
Easy backup: love this feature from Aperture, but it only works for managed libraries.
Easily navigate a chronological library: three decades of digital photos and counting
Smart albums (by any metadata just like Aperture)
Mapping: I geotag everything and love exploring my map (please allow it to go fullscreen, not tiny windowed like Aperture)
Stacks: for marking a set of photos as related (ex: to remember to make a panorama)
Versions: unlimited versions from non-destructive edits
Importing all my work from Aperture would be nice, but honestly it's just a viewer for me. I'd be very happy with a tool that just makes enjoying my photos and managing thousands of them a breeze.