ITreviewed posted a review on the Adobe Photoshop CS4 Extended

With every release of Photoshop you wonder how Adobe can possibly improve this awesome image editor. Photoshop CS4 is a performance powerhouse and packs in tons of enhancements, a wealth of non-destructive editing features, numerous tool tweaks, and an improved interface that helps reduce panel clutter. Make no mistake, Photoshop CS4 is not for casual photo hobbyists. Designed primarily for photographers and imaging professionals, the software is very expensive and has a huge learning curve - just check out the range of tutorial books in your local bookstore and the number of training courses available throughout the world! Sadly, the software's text support is still slow, awkward, and often produces subpar output because it's bitmapped opposed to vector text. The only workaround to get professional results is to import the final image into a vector-based program such as Adobe's Illustrator or Corel's CorelDraw, then add crisp vector characters to your picture. If you want the best, don't mind the cost, and have the hardware to run it, Photoshop CS4 Extended is the best. For most of us not needing the special 3D features of Photoshop CS4 Extended, Photoshop CS4 is just the ticket.

Adobe Photoshop CS4 Extended Review