Wow, it's a tough decision which to process in. Lightroom or Aperture, that's for sure. One on hand you have the king of the block and on the other you have a infrastructure that's inherent within the Apple system, and works fluently with other programs such as iPhoto. Here's an image which has been processed in both Aperture with a black and white preset, which was easily found on the internet with little tweaking and the other worked on in Lightroom and then finished in Photoshop. Both look pretty darned good to me as a finished article.
I'm struggling to pick a winner. The Lightroom image has a touch more detail bought out through the processing, but maybe a little more noise (graining), whilst the Lightroom image has a more pleasing tone to it.
It's not simple to choose between the two that's for sure. As I've used Lightroom for a couple of years or so now, the workflow is more intuitive to me, however I think with more practice I could easily get used to what Aperture has to offer. I also think it offers more flexibility to the Fuji RAW files and how it handles them, although Lightroom is catching up fast.
So, I can't call a clear winner at present, I think I may work with both - using Aperture more selectively on some images to see how it feels, and using Lightroom for my more day to day images.
What do you think?