Most conditioners have separate digital and analog outlets since the filtering is usually more aggressive on digital components than analog.The main reason for separate outlets for digital is so that they are isolated from analogue components. Digital, especially those using wall-warts may return noise back to the mains.
I've never used a power strip with separate filters for digital, although I've used digital only power cords and didn't like how the filters affected the sound. The most important feature is isolated receptacles.
My power conditioner has 4 duplexes (8 outlets), all are being used.