Well a resolution in dpi doesn't make much sense in terms of digital images since there is no intrinsic size.
But there is an intrinsic size when it's output as a raster image, in our case, 72dpi at approximately 640x480 pixels (various cropping in the photomerges changes the dimensions). Pretty much the maximum the DVDs allow for, as they're not HD and the video was meant for older television sets in the 480p range.
You'd be surprised how low resolution billboard photographs are.
That's because billboards are viewed from a distance and generally only for a few seconds at a time.
And, all of this does matter for print. It's the difference between the example on the left vs. the example on the right*:
But, if artifacts and pixelization don't bother you, feel free to print them out
I'm just used to raster images that are meant for "print" being at least 300dpi and CMYK.
Now, there are ways to cheat around this a little. If the image is detailed enough, you can try to get away with importing it into Illustrator and running a high fidelity live trace on it to make it a vector, which is scalable and not bound by the limitations of a raster image. I tried that with the skyline image, and it turned out okay (not perfect):I exported the graphic into a PDF which you can all download here for printing (10mb).* Of course if you're reading this on an iPod/iPad odds are every image on this site looks like that, as iOS and others are displaying at a higher resolution than 72dpi.
And, just so we're not drifting too far off topic (as much as I'd like to digress into my love/hate relationship for graphic design related issues), does anyone else recall anymore instances of pans in episodes?