A while ago I created a big page on Squidoo about eBook Reader Comparisons. It lists the main tech specs for what I consider to be the most popular eReader devices. It mainly focuses on E-Ink devices but I also included some information on the iPad as well. I update it at least once per month, and I plan to keep adding new models that come out, while rotating off any outdated models.
If you have a Squidoo account, please Like it (and any of my other lenses that you like). You can also Tweet it or Share on Facebook. I’d appreciate it!