Couple of added Thoughts.....
Inkjet printers such as the Epson R1900, (and others in its price range) have the capability to produce exhibition quality photographic prints. When, as Jobeard has pointed out, they are paired with the correct type of photo quality papers.
You do not actually need "Photoshop CS" to do this. For photo printing, Adobe's "Photoshop Elements" (currently on version 7), is sufficient, @ around $100.00 instead of $700.00.
Photoshop CS adds the capability to deliver files to a production lithographic press, or "rotogravure" if you will. This is because it has the capability to edit in "CMKY" mode, and has color profiles for "Pantone Inks", which are the printing industry standards.
I suppose in plain English, you can print high quality photos with the less expensive "Elements", and you could deliver the files to print "People Magazine", from your desk with Photoshop CS.
So yes, print quality is partially software dependent, much of which comes from the color management abilities of the programs mentioned.