The arduino yun [1] combines an linux-based SoC with a microcontroller on a single board. So you can have both, networking and applications in practically any language, and an internal interface to a microcontroller.
For only accessing a rs232 serial port over ethernet, there are easier solutions. But if you need multiple of such ports, sensor access, etc. its quite a nice combination.
Yes, the paper is not peer-reviewed yet. However, given the time it takes to go through a review process, it is not surprising that the authors publish a techreport on arXiv.
In any case, this is much better than what anybody anticipated.
For only accessing a rs232 serial port over ethernet, there are easier solutions. But if you need multiple of such ports, sensor access, etc. its quite a nice combination.
[1] http://arduino.cc/en/Main/ArduinoBoardYun?from=Main.ArduinoY...