I could not disagree more, but I suspect it's because I use PDFs very differently from how you do.
PDF is valuable because if you need a certain page layout, PDF can guarantee that layout. It's a freeze on the information contained in the document, as it relates to all the other information.
I have many graphics-heavy books (i.e., comic books) that are in PDF. I would be extremely upset if eReader manufacturers just announced they weren't going to support them because of an ideology about what is/isn't a true eReader format.
Saying "render it in HTML" does not fix the issue in all cases where PDF is necessary. Heck, I don't think it would fix the issue in MOST cases.
(Reminds me of those arguments that a color eReader isn't a REAL eReader because it's not in eInk. Pffft.
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