I don't want to start a flame war but I'd like to invite those who have both a Q7 and a Kindle, Kindle 2, and/or Kindle DX to chime in about how they compare. However, I must admit I'm biased toward the Q7.
Consider the hardware.
Some of the advantages of the Q7 include the full-size SDHC slot, the two USB ports, color touch-screen display, WIFI, etc. Of course, Whispernet is a big plus for the Kindle family. Auto screen rotation on the DX is very cool and actually useful for web browsing. However, I much prefer being able to attach an external USB keyboard over using any of the three different Kindle keyboards.
Consider the software.
You can run all sorts of software on the Q7. Right out of the box, the Q7 comes with a word processor, spreadsheet, drawing program, etc. Also, adding stuff like Flite and Mirage is fairly easy to do but this requires some tech skills.
The Kindles are part of a closed ecosystem but the Kindle Store makes this ecosystem very useful. There's nothing like being able to order a bestseller and have it delivered in under a minute. However, I've been in areas without Whispernet coverage but can still use the Q7's WIFI at the local library or another free hotspot.
Thanks to Google Books, there are over a million public domain works available for the Q7. Midori works well with Google Books for online reading and PDFs are available for offline reading.
One of the big disappointments I've had with the Kindle DX is how it handles PDFs. I know some people here are complaining about Evince but the PDF reader built into the DX is much worse. Evince on the Q7 will open PDFs that generate error messages on the DX.
One of the surprises in comparing the DX to the Q7 is that the DX is actually heavier. Ounces matter. I prefer either the Q7/Kindle 2 over the DX for extended reading.
Also, I think the DX is more awkward to use. The Q7 can be either a one-handed or two-handed device while the DX seems easiest to use with two hands.
For $489, I expected a lot more from the DX. For $190 plus shipping, I think the Q7 is a great bargain.
What are other people's thoughts?