[andy153]

You are right again Adey - CS 3 has these various corrections available but I actually started with Photoshop 7 for a long time. Because of the price in those days I started looking at "Toys" that would do things that were limited or poorly done in Photoshop. And as Photoshop has progressed so have the "Toys". The beauty of DXO is that it is specific to various lens and body combinations - there are different algorithms for the D300 and the D2x both with the Sigma 10-20 etc. Its BIG drawback is that it alters the original if as they suggest you batch everything through DXO to start. It reads the EXIF to make its choices - so for DXO I create a separate DXO Library to my Aperture Vaults. Also the new Beta DXO 5 is quite slow and my machine is a dual chip Mac with 8.5 Gb RAM.
As Photoshop and my "Toys" evolve no doubt some of them will become superfluous as Adobe take some of the functions to themselves - but in the mean time I find them fun.