"Interesting, thanks. As far as I can tell, it's possible to convert PDFs to the Kindle's native format, any idea if this improves the situation?"
Yes. I use mobipocket creator [1] to convert pdf files to the mobi format. It's free and works pretty well for documents with one column. For papers with multiple columns (like those from journals) I use papercrop [2] to slice the pdf in smaller parts so I can read in my (non-dx) kindle 2.
It just convert the chunks to an image (the final format is a PDF as well). The result is a little bit hacky, but it works. If your goal is to catch up with your reading pile, so it may work for you. On the other hand, if you need/want to go over every single detail (tables, formulas, etc), it may not work so well. As usual, YMMV.
[Actually, mobipocket creator seems to be not too bad at converting multi-column documents. The problems I had converting academic papers were tables and math, and not the fact they had more than one column]
Yes. I use mobipocket creator [1] to convert pdf files to the mobi format. It's free and works pretty well for documents with one column. For papers with multiple columns (like those from journals) I use papercrop [2] to slice the pdf in smaller parts so I can read in my (non-dx) kindle 2.
[1] http://www.mobipocket.com/en/downloadsoft/productdetailscrea...
[2] http://code.google.com/p/papercrop/
edit: small fixes