Earlier today Apple released printer driver updates for Epson and HP printers. these packages include the latest drivers for supported printers and scanners from these companies, and are available for OS X 10.6 only.
The updates are available in full at the following locations:
If you have a printer you have not used with your system, you can check the list in the following knowledgebase document to see whether or not it is fully supported in OS X: http://support.apple.com/kb/HT3669
Keep in mind that if you have a printer installed and working, you might consider against installing these updates. You only need the one driver for your particular hardware, and these updates will include all drivers. Additionally, some people have found printer driver updates to adversely affect their setups, resulting in bizarre problems.
Our recommendation is to not install a driver update unless your current one is not working properly.