We’ve known about Microsoft’s digital journal Courier since late last year and details are finally starting to leak, reports Engadget.

Engadget writes, “Courier will function as a “digital journal,” and it’s designed to be seriously portable: it’s under an inch thick, weighs a little over a pound, and isn’t much bigger than a 5×7 photo when closed. That’s a lot smaller than we expected — this new picture really puts it into perspective — and the internals apparently reflect that emphasis on mobility: rather than Windows 7, we’re told the Courier is built on Tegra 2 and runs on the same OS as the Zune HD, Pink, and Windows Mobile 7 Series, which we’re taking to mean Windows CE 6.”

The Courier is designed to act like Microsoft’s e-reader with primary focus on information input and sharing with a pen-based input mechanism. The entries will look like blog posts with comments. It is also expected to have a headphones jack for media playback and a built-in camera. It’s quite the device, to the least.

There’s no word on pricing yet, and the availability is scheduled for some time in Q3-Q4 timeframe.