Printer test: April 2005 on Epson R800 printer as a result of discourse with Qimage's Mike Chaney.

I downloaded a test chart from DP Review, used levels to increase contrast to reasonable amounts, re-scaled (not resampled) to an arbitrary 300ppi and used modest USM to prepare this base file.
I resampled this to create other images at both 360ppi & 720ppi. Out of PS I printed all 3 variants at PhotoRPM on high quality glossy paper on my Epson R800 printer.
Between 300 and 360ppi there was a HUGE change that was visible to the naked eye even under casual observation.

To allow the reader to see what I printed, I had to scan the resultant prints. I did this at an appropriately high resolution and interpolated them down to approximate what I see with my eyes at about 12 inches away in decent lighting.

Moiré is omnipresent in the majority of the 300ppi portions that I’ve boxed in blue.

In the 360 and 720 ppi portions that are boxed in red, I find the 720ppi image is ever so slightly better in regard to moiré. Here the moiré manifests itself as a hint of a vertical shadow banding in the web image as well as in the real printout.

The sections boxed in yellow are especially interesting and significant because the moiré is inherent in the original file itself and a result of the camera-sensor/lens/test-chart interaction.

Moral to the story: If you use an Epson printer, it's best to resample to 360 ppi or better yet 720ppi to prevent unwanted issues.

EDIT May 2017: I've been though a few Epson printers since this original test 12 years ago.
The printers have gotten better gamut-wise and the driver interface has changed, but I have no reason to believe that there would be substantive differences if i redid this test today.
The Epson drivers still appear to be using Nearest Neighbor or something similar to resample to the printer's native resolution (inevitably 720 ppi).