Thanks to JiHO, bulia byak, and minombresbond for responding. I'm replying to the digest so please forgive me if I address all responses at once.

In a nutshell, the latest version of Inkscape does in fact work very well for rasterizing blurs and including them in pdfs at the proper resolution. The only issue I ran into when I did a test print this afternoon was that the rasterized blurs gave off a bounding box effect when printed that didn't show up (to my eye, at least) when the pdf was viewed on screen. The bounding box effect was, specifically, a discoloration of of the background under or behind the bounding box. Is there some setting or technique for eliminating this effect? If so, then this approach would work beautifully for getting what's on screen onto the printed page.

My back-up approach will be to output pngs and then use Scribus to layout the cover (though I'll probably skip the CMYK step suggested by minombresbond since Amazon's POD service apparently doesn't require CMYK).

And, to answer JiHO, I have both Ubuntu Linux and Windows XP available. I prefer Ubuntu, but do some of the color work on the XP box because it has a superior monitor. (My Ubuntu is on a laptop with a so-so lcd monitor.)

Anyway, thanks again for the help.

Matt Jordan