Hey...
I just encountered what may be a bug in the PDF writer posted on BeBits. I accidently went "save as" on a Gobe Productive and overwrote my schedule.pdf file as a GP file. GP took over the MIME type and the icon changed. So, oops, I went and saved somewhere else, and then printed using the PDF writer driver, saving over top of schedule.pdf again. But the driver didn't take over the MIME type like GP did, so even though it wrote a PDF file over top schedule.pdf, I could no longer launch it, because it would be opened in Gobe.