I'm aware this topic has cropped up before.
However most of the answers were Windows specific. Right now I'm using the software that came with my camera and it works fine. However, it has one serious drawback : it doesn't process pictures taken with cameras of other brands. I'm mostly stitching pictures together to create panoramas. Price is not an issue and I've tried Photoshop's built-in pano tool but it's a little bit elementary.
Auto-Stitching and HDR support is really what I'm looking for.