Beagleboard for Digital Signage/Out of Home Media? How?

I am final year student of Bachelors in Computer Science. I know high
level app development using c# 2008, java SE, c++ and c. I have little
exposure to linux and embedded systems. I want to use the beagleboard
I won in a lucky draw at beagleboard event as an opportunity to learn
embedded systems.
I have read in many websites and seen in many ppts that beagleboard
can be used to make digital signage.
I want to do such a thing. I want the content to be changeable and
designable remotely from a XP machine

How do I start on such a project? Please mention the APIs, Languages I
need to learn.

There is an open source digital signage software called concerto. Take a look there. the signage nodes are currently x86 based. Maybe you can port it over to ARM.