I work at BN, so I'm probably biased, but if you want an ereader that's eink, I'd check out the new nook simple touch. Full touch screen using the same pearl eink screen as the Kindle, twice the battery life of the Kindle, has a native epub reader (no converting necessary), you can borrow from digital libraries, and it has an expandable memory card slot so that you can add more space to it.

Your local Best Buy should have demo units of both the nook and the Kindle. I'd recommend going in and actually using one for a bit to see which one you like best. If you go into your local BN, they're full working models so you can test the shop as well (if it doesn't work at Best Buy).