It already uses MySQL locally as the database.
....
Now that we have forked and are in linuxMCE world - I am not sure if the sqlcvs server still works and does the automatic updating. If Paul is reading this he might be best placed to answer. If it is not, it would be a good thing to bring back as it allows new devices to quickly become available - or even updates to existing ones. I am not sure how this is meant to occur otherwise - I guess it would need to be release based.
As far as I know, the LinuxMCE is still using the Pluto sqlCVS server - it was not separated yet. (This information is from Paul's post in separate thread)