If you have hardware that supports HDMI (both your computer and your receiver), you can use HDMI to transport uncompressed multi-channel audio (up to 6-8 channels) and don't need the a52 plugin. Of course, if you are stuck to older hardware without HDMI, that's no solution, but I guess a lot of people will be able to use HDMI nowadays.
If you have hardware that supports HDMI (both your computer and your receiver), you can use HDMI to transport uncompressed multi-channel audio (up to 6-8 channels) and don't need the a52 plugin. Of course, if you are stuck to older hardware without HDMI, that's no solution, but I guess a lot of people will be able to use HDMI nowadays.