Is Amazon’s Kindle about to become an also-ran in the e-book sweepstakes? Not exactly, but several new or planned digital readers are pushing the design envelope as they look for an edge over the Amazon original. Plastic Logic shows off its ultra-slim Que reader this morning, while iRex is promising that a “dramatically different” model is on the way. The big news today, though, is the Alex, a dual-screen reader from Spring Design with a 6-inch e-ink screen on top and a 3.5-inch color touchscreen below for web browsing. It looks a whole lot like the leaked photos of the much-anticipated Barnes & Noble ebook reader, which is expected to be unveiled tomorrow. And in case you were wondering, B&N got FCC approval for an e-book device last month.