Ben Rudolph: Today is the grand opening of the Microsoft Store in Bellevue Square Mall, and it’s also the first time you’ll be able to walk into a store and get some play time with the Dell Inspiron duo, Dell’s completely unique take on combining a multi-touch touchscreen and a traditional keyboard. I was lucky enough to have worked with the duo for a few days in the weeks leading up to launch, and wanted to share my take on this very different approach to the “touch vs. type” debate…