I think what you're both looking for is something more like this.
According to the manufacturer they developed it for business users. Whereas many of the current eReaders on the market are geared more toward casual/academic users. Unfortunately (and probably predictably) it's not scheduled for release until later this year, and there is no listed price as of this writing.
I personally went with the PRS 700 for the note taking. The Kindle 2 offers notation; however, PDFs are a pay-per-convert option. And, the cursor navigation/highlighting is much like the old IBM Thinkpad eraser stick (of which I was not a fan).
Being a web developer/designer I tend to type pretty fast - and found the delayed response of the PRS 700 keyboard a little annoying. Then I noticed that it caches keystrokes. So, the slowness was mainly me slowing down to wait for the reaction. Now, I just type away and let the e-ink catch up to me - working well so far (and I'm a notation junky).
PDFs on the PRS700 get a little wonky with larger font sizes with regard to line breaks and the like. Would almost recommend converting the PDFs to LRF - using Calibre or similar software. However, for infographics - I really don't think the screen size will be very accommodating.