It would not be hard. I have already investigated it. The biggest programming issue is what to do with the commands when they come into the computer. If you have someone who can get the commands from a USB relay to a PC key stroke, the integration is easy. You would only use the buttons to activate relays. I already have had them integrate the outputs to the relays in the front end.
I just don't miss the buttons, I thought I would, but I really don't.
On a side note.. I have been using a new front end that someone created.. it is very nice. Here are a few screen shots of it.
There are some things I still want to change on it, but it is very nice overall.
I have also been using some free software to compress movies from my personal DVD's and have about 15 movies now stored on my HDD for viewing. It is really nice.