Nook HD >>> Kindle Fire HD.

The charge cables on the Nook HD and HD+ have 30 pin cables like (but not exactly the same as) the old iPod cables. They don't use the extended microUSB tip anymore -- haven't had any problems with mine. However, the new Nooks use Android 4.0 and Android changed how they handle remote file systems -- it now treats the Nook HD or its SD card as a media drive rather than a regular external drive so I can no longer manage the Nook library natively with Calibre. Battery life is excellent, speed is much better than the Nook Tablet.